bluuebunny/crossref_metadata_2025 huggingface dataset:
X-ray powder diffraction study on ErNi2Ge2
Authors: Nong Liangqin , Zeng Lingmin
Published: January 2013

An X-ray diffraction pattern for ErNi2Ge2 at room temperature is reported. ErNi2Ge2 is tetragonal with lattice parameters a=4.0191(2) Å, c=9.7643(2) Å, space group I4/mmm, and Z=2. The lattice parameters derived from Rietveld analysis agree well with the results of a least-squares refinement.
A practical approach to Rietveld analysis. Comparison of some programs running on personal computers
Authors: Karanović Lj. , Petrović-Prelević I. , Poleti D.
Published: January 2013

Three computer programs for Rietveld analysis DBWS-9411, HILL-93.06, and FULLPROF-3.1 have been tested and compared using data for two samples of different complexity, spinel, and anglesite. The investigation shows that results are “program dependent.” The obtained R indices for spinel are in the ranges 10.60%–13.26%(Rwp) and 3.15%–5.25%(RB). Similarly, the ranges for anglesite are 9.76%–14.06%(Rwp) and 2.15%–5.06%(RB). Some atom and displacement parameters are significantly different, too. In attempt to define the standard procedure for Rietveld analysis, three parameters, n, BKPOS, and RLIM were examined. It was found that the most appropriate values for them are: n=8–10, BKPOS=90°, and RLIM=40° 2θ. Using Fourier filtering for background modeling, significantly lower R indices were obtained in comparison to polynomial and interpolated background. At the same time the great numbers of atom and cell parameters agree within ±3σmax and e.s.d.'s were identical or lower than those achieved for polynomial and interpolated background. It was found that the function given by Bérar and Baldinozzi (1993) (J. Appl. Crystallogr. 26, 128–129) much better described asymmetric peak profiles at low 2θ angles. This function and Fourier filtering were implemented only in FULLPROF, which has more possibilities and some advantages over the other two programs. In addition, the peak shift parameters (sample displacement and transparency) were tested. It was shown that under present circumstances these parameters do not have much effect on atom parameters and R indices. However, differences in unit cell parameters were considerable greater, most probably because of the large correlation between zero-point, lattice, and peak shift parameters.
On the space group of garronite
Authors: Artioli Gilberto , Marchi Maurizio
Published: January 2013

The crystal structure of the natural zeolite garronite from Goble, Oregon has been refined using high resolution synchrotron X-ray powder diffraction data. Garronite has the same tetrahedral aluminosilicate framework as gismondine [GIS], and earlier structural models indicated a strong tetragonal pseudosymmetry. Proposed models in the literature were based on the I4¯m2 and I41/a space groups, on account of symmetry lowering from the topological I41/amd space due to partial cation/water molecule order in the zeolitic cavities. Test structure analysis has been performed in all possible space subgroups including monoclinic space groups, and the refinement has been successfully carried out in space group I2/a (C2/c). The resulting monoclinic structure model is to be preferred over the tetragonal ones on the basis of: (1) lower agreement indices of the refinement; (2) a chemically sound framework geometry; and (3) a more satisfactory interpretation of the Ca atoms coordination in the extraframework cages.
Cohen's method revisited
Authors: Spinolo Giorgio , Maglia Filippo
Published: January 2013

The subject of the paper is the old and well-known linear least squares method for determining the lattice dimension of a crystalline phase from the peak locations of a powder diffraction pattern. Approximations, limits, and extensions of the method are discussed with reference to the assignment of hkl indices to an experimental multiphase pattern.
Powder diffraction data and Rietveld refinement for Y-doped (ZnO)5In2O3
Authors: Pitschke W. , Koumoto K.
Published: January 2013

Indexed X-ray powder diffraction data are reported for the homologous compound (ZnO)5(In1−xYx)2O3. The structures of (ZnO)5In2O3and of (ZnO)5(In1−xYx)2O3were refined by the Rietveld technique on the basis of the space groupR3¯m. Refined unit cell dimensions area=3.3285(1) Å,c=58.127(2) Å,V=557.71(3) Å3,Dx=6.11g/cm3,Rwp=10.52,RB=8.56 for (ZnO)5In2O3, anda=3.3505(1) Å,c=57.863(1) Å,V=562.53(2) Å3,Dx=5.97g/cm3,Rwp=9.05,RB=6.94 for (ZnO)5(In0.8Y0.2)2O3. The structure of (ZnO)5In2O3was shown to be isostructural with (ZnO)5LuFeO3.Y3+ions were determined to be arranged at the 3a-metal sites substituting forIn3+ions.
New X-ray powder diffraction data for two triborates CsB3O5(CBO) and TlB3O5(TBO)
Authors: Touboul M. , Pénin N. , Seguin L.
Published: January 2013

Precise X-ray powder diffraction patterns of two isostructural triborates, CsB3O5(CBO) and TlB3O5(TBO), have been collected on a D5000 diffractometer with a primary monochromated beam (λ CuKα1=1.5406 Å). Refinement of indexed reflections in the space group P212121 led to: a=6.201(1) Å, b=8.514(2) Å, c=9.176(2) Å, Z=4, Dx=3.363 for CBO and a=5.2156(4) Å, b=8.2659(6) Å, c=10.2240(9) Å, Z=4, Dx=4.773 for TBO. The Smith–Snyder figures of merit are F30=53.0 (0.0101, 56) for CBO and F30=112.9 (0.0074, 36) for TBO. These values are much better than the previous ones published in Powder Diffraction File.
Subsolidus phase relations in La2O3–Bi2O3–CuO
Authors: Chen X. L. , Eysel W.
Published: January 2013

The subsolidus phase relations in the ternary system La2O3–Bi2O3–CuO at 900 °C were investigated by X-ray powder diffraction. A new binary compound, Bi2La4O9, was found, as well as a binary and a ternary solid solution series, Bi1−xLaxO1.5 (0.16≤x≤0.33) and La2−xBixCuO4 (0≤x≤0.11), respectively.
Quantitation of crystallinity in substantially amorphous pharmaceuticals and study of crystallization kinetics by X-ray powder diffractometry
Authors: Surana Rahul , Suryanarayanan Raj
Published: January 2013

The first object was to develop an X-ray diffractometric method for the detection and quantification of crystalline sucrose when it occurs as a mixture with amorphous sucrose. Standards consisting of amorphous sucrose physically mixed with 1 to 5 weight percent crystalline sucrose were prepared. The sum of the background subtracted integrated intensities of the 12.7°2θ (6.94 Å) and 13.1°2θ (6.73 Å) sucrose diffraction peaks were linearly related to the weight percent crystalline sucrose. The limits of detection and quantitation of crystalline sucrose were 0.9% and 1.8% w/w, respectively. The second object was to study the kinetics of crystallization of sucrose as a function of temperature (at 102, 105 and 110 °C under a water vapor pressure of 0 Torr) and water vapor pressure (17.4, 19.8 and 21.4 Torr at 27 °C). In all cases, the crystallization kinetics was best described by the Avrami-Erofe’ev model (three-dimensional nucleation).
Rietveld full-profile quantification of Portland cement clinker: The importance of including a full crystallography of the major phase polymorphs
Authors: Taylor J. C. , Hinczak I. , Matulis C. E.
Published: January 2013

Crystalline phases present in the three NIST SRM Standard Portland cement clinkers 8486, 8487, and 8488 have been quantified from XRD powder patterns, (CoKα radiation), using the full-profile Rietveld method. Included in the Rietveld refinement are rhombohedral (R), monoclinic (M), and triclinic (T) crystal polymorphic forms of C3S, as well as crystal polymorphs of C2S and C3A. It is necessary to specify the phase crystallography including polymorphs, because of the extreme superposition of alite and belite XRD lines in the clinker patterns. Unsatisfactory results occur when only one or two of the C3S polymorphs are used in the Rietveld quantification; best results occur when all three polymorphs for C3S are included. The latter are called RMT-type refinements. The Rietveld full-profile XRD method is as precise as the microscope point-counting (MPC) method, but much less labor-intensive. The Rietveld method can quantify the C3S phase polymorphs, as well as total C3S. Rietveld and MPC methods give the same phase weight percentages for the three NIST standard clinkers. Calculated oxide weight percentages obtained from Rietveld phase weight percentages agree well with oxide percentages determined by XRF analysis. Bogue mineral weight percentages do not agree with Rietveld or MPC data, while transformation of the Bogue mineral percentages to oxides does not compare well with XRF analysis.
A temperature-dependent powder diffraction study of chromium lanthanum nitrate, LaCr(NO3)6·12H2O
Authors: Gobichon A.-E. , Auffrédic J.-P. , Louër D.
Published: January 2013

The new phase LaCr(NO3)6·12H2O was synthesized from a nitric acid solution. The symmetry is trigonal with the parameters a=10.9564(4) Å and c=16.835(1) Å [V=1750.2(2) Å3, space group R-3]. The thermal decomposition, studied by temperature-dependent X-ray powder diffraction and thermogravimetry, gave successively the cubic phase LaCr(NO3)6·6H2O [a=12.301(1) Å, space group P213] and the chromate(V) LaCrO4. The reduction of LaCrO4 to LaCrO3 occurred at a temperature depending on the oxygen pressure in the reaction atmosphere.
A mineralogical study of a natural pyrophyllite
Authors: Bentayeb A. , Masson O. , Noack Y. , Yacoubi A. , Nadiri A.
Published: January 2013

A chemical and mineralogical investigation of a Moroccan pyrophyllite is presented. X-ray powder diffraction has been largely used for phase identification and crystal symmetry determination. It is shown that this mineral has a triclinic symmetry with cell parameters: a=5.160 Å, b=8.993 Å, c=9.360 Å, α=90.77°, β=100.57°, and γ=89.71°.
X-ray powder diffraction study of CuInSeTe
Authors: Rashmi  , Suri D. K.
Published: January 2013

CuInSeTe was synthesized by the melt and anneal technique. The compound crystallized in the chalcopyrite structure having space group I4¯2d with Z=4. Complete X-ray powder diffraction data were obtained and the unit cell parameters a and c, X-ray density and u parameter were calculated. These are a=0.5987(1) nm, c=1.1979(4) nm, Dx=5.96×103kg/m3, and u=0.2498. Atomic positions in the unit cell are proposed.© 2000 International Centre for Diffraction Data.
Chemical preparation of aluminum borate whiskers
Authors: Gönenli I. Erkin , Tas A. Cüneyt
Published: January 2013

Aluminum borate (9Al2O3·2B2O3) whiskers were chemically synthesized in potassium sulphate flux by using the starting chemicals of aluminum sulphate and boric acid. The synthesis temperature of 1075 °C was found to be the optimum with respect to whisker morphology. A tentative X-ray diffraction (XRD) pattern was suggested for the whiskers produced after heating at 1150 °C. The product purity, phase composition, and whisker morphology were investigated by XRD, energy dispersive X-ray spectroscopy, and scanning electron microscopy, respectively.
Powder X-ray data for melatoninC13H16N2O2
Authors: Caminiti Ruggero , Ortaggi Giancarlo , Mazzei Raffaele Antonio , Ballirano Paolo , Rizzi Rita
Published: January 2013

Powder X-ray diffraction data of melatoninC13H16N2O2were collected on a conventional X-ray powder diffractometer: the monoclinic cell parameter area=7.7416(8) Å,b=9.2897(9) Å,c=17.1444(16) Å, β=96.756(9)°, volume 1224.4(3) Å3(space groupP21/c). The strongest lines are (d(Å),I/I0) 8.161 (100), 5.411 Å (46), 3.412 Å (34), 4.668 Å (33), 4.645 Å (25), 3.554 Å (22), 3.668 Å (16), and 4.483 Å (14). Reported intensities are validated by Rietveld analysis. The data consist of measured positions and intensities and cover an angular range up to 60° 2θ: experimental, calculated, and difference patterns are also reported.
Powder diffraction data of semimagnetic semiconductors Hg0.80Mn0.20S, Hg0.89Fe0.11S and Hg0.98Co0.02S
Authors: Paszkowicz W.
Published: January 2013

Powder X-ray diffraction data are reported for semimagnetic semiconductor Hg0.89Fe0.11S and Hg0.98Co0.02S crystals grown by the Bridgman method and for Hg0.80Mn0.20S crystal synthesized by a solid-state reaction method. The crystals have the sphalerite structure of metacinnabar (sphalerite-type high-temperature polymorph of HgS, space group F4¯3m). Phase analysis does not show any trace of other phases. The lattice parameters of the studied samples are a=5.803 20(5) Å, 5.8063(1) Å and 5.839 80(6) Å, respectively. The calculated density is reported.
Crystallographic studies of plant waxes
Authors: Meusel Iris , Barthlott Wilhelm , Kutzke Hartmut , Barbier Bruno
Published: January 2013

Plant surfaces are mostly covered with microscopic layers of wax which exhibit characteristic morphologies, visible under high magnification. Waxes belonging to three different types were investigated. Powder data of seven natural and three recrystallised waxes as well as of two isolated compounds are presented. The mainly crystalline nature of the studied plant waxes is proved. The correlation between morphology, chemical composition, and powder patterns is discussed.
Rietveld quantitative X-ray diffraction analysis of NIST fly ash standard reference materials
Authors: Winburn Ryan S. , Grier Dean G. , McCarthy Gregory J. , Peterson Renee B.
Published: January 2013

Rietveld quantitative X-ray diffraction analysis of the fly ash Standard Reference Materials (SRMs) issued by the National Institute of Standards and Technologies was performed. A rutile (TiO2) internal standard was used to enable quantitation of the glass content, which ranged from 65% to 78% by weight. TheGSASRietveld code was employed. Precision was obtained by performing six replicates of an analysis, and accuracy was estimated using mixtures of fly ash crystalline phases and an amorphous phase. The three low-calcium (ASTM Class F) fly ashes (SRM 1633b, 2689 and 2690) contained four crystalline phases: quartz, mullite, hematite, and magnetite. SRM 1633b also contained a detectable level of gypsum, which is not common for this type of fly ash. The high-calcium (ASTM Class C) fly ash, SRM 2691, had eleven crystalline phases and presented a challenge for the version ofGSASemployed, which permits refinement of only nine crystalline phases. A method of analyzing different groups of nine phases and averaging the results was developed, and tested satisfactorily with an eleven-phase simulated fly ash. The results were compared to reference intensity ratio method semiquantitative analyses reported for most of these SRMs a decade ago.
X-ray powder diffraction data for zinc molybdate, Na(OH)Zn2(MoO4)2·2.5H2O
Authors: Palacio Luz Amparo , Saldarriaga Carlos
Published: January 2013

Powder diffraction data were collected for a synthetic zinc molybdate of composition Na(OH)Zn2(MoO4)2·2.5H2O. The material is monoclinic, space group C2/m, with a=9.4543(12), b=6.3492(7), c=7.6453(11), β=115.899(13), and V=412.83 Å3.
Crystal structure of the monoclinic perovskite Sr3.94Ca1.31Bi2.70O12
Authors: Wong-Ng W. , Kaduk J. A. , Huang Q. , Roth R. S.
Published: January 2013

The crystal structure of the low-temperature oxidized form of Sr49.5Ca16.5Bi34O151 has been determined using a combination of neutron, synchrotron, and laboratory X-ray powder diffraction data. The structure is pseudo-orthorhombic; systematic absences and successful refinement indicated the true structure to be monoclinic, with space group P2l/n. Structural refinement using only neutron powder data yielded the lattice parameters a=8.38 898(29) Å, b=5.99 334(21) Å, c=5.89 586(20) Å, β=89.997(8)°, and V=296.43(3) Å3. This compound is a distorted perovskite phase [described in the perovskite ABO3 formula as Sr(Bi0.7Ca0.3)O3] with ordering of the M-site cations, resulting in the formula A2MM′O6. In this ordered structure, the A sites are solely occupied by Sr, the M sites mainly by Bi, while on the M′ sites Bi and Ca are distributed in an approximate ratio of 2:3. The MO6 and M′O6 octahedra share corners, and are tilted with respect to the neighboring layers with an angle of ∼15° around all three axes. The tilt system symbol is a+a−a− according to Glazer notation. All Bi ions are in the 5+ oxidation state.
The crystal structures of CeSiO4 and Ca2Ce8(SiO4)6O2
Authors: Skakle J. M. S. , Dickson C. L. , Glasser F. P.
Published: January 2013

Two new solubility-limiting phases relevant to nuclear waste disposal are reported, namely CeSiO4 and Ca2Ce8(SiO4)O2, produced by hydrothermal synthesis at 180 °C. X-ray diffraction data are presented for both compounds. Rietveld refinement was performed for each of these phases. CeSiO4 was confirmed to be a zircon structure type, with space group I41/amd, unit cell type="bold">abold=6.9564(3), type="bold">cbold=6.1953(4) Å. Bond lengths for SiO4 are in excellent agreement with published values; Ce4+ is coordinated to eight oxygen atoms with four regular and four short bonds. Ca2Ce8(SiO4)O2 was shown to have an apatite structure, with space group P63/m and unit cell type="bold">abold=9.4343(3), type="bold">cbold=6.8885(4) Å. The unit cell and bond lengths were found to be slightly smaller than would be expected from other lanthanide-containing analogs; possible reasons for this are discussed.
Methods of Producing Standard X-Ray Diffraction Powder Patterns
Authors: McMurdie Howard F. , Morris Marlene C. , Evans Eloise H. , Paretzkin Boris , Wong-NG Winnie , Hubbard Camden R.
Published: January 2013

Patterns useful for identification are obtained by automated diffractometer methods. The lattice constants from the experimental work are refined by least-squares methods; reflections are assigned hkℓ indices consistent with space group extinctions. Relative intensities, calculated densities, literature references, and other relevant data are included.
The X-Ray Crystallography of Rosasite From Tsumeb, Namibia
Authors: Roberts Andrew C. , Jambor John L. , Grice Joel D.
Published: January 2013

Crystals of green to bluish green rosasite from Tsumeb, Namibia are monoclinic, space group P21/a, with refined unit-cell parameters a = 12.873 (3), b = 9.354 (3), c = 3.156 (2) A, β = 110.36 (3)°, V = 356.3 (5) A3 and a:b:c = 1.3762:1:0.3374, with Z = 4 and Dx = 4.15 g./cm.3. Crystals are twinned by 180° rotation about a*. A fully indexed powder pattern is presented. Electron-microprobe analyses, average (wt. %): Cu 32.9, Zn 23.7; this suggests an analytical formula of (Cu1·18 Zn0·82) (CO3) (OH)2. The rosasite is optically biaxial negative, α = 1.673 (1), β = 1.796 (3), γ = 1.811 (3), 2Vx = 33 (5)° (calc. 36.4°), with X = c, Y = a* and Z = b.
Applications of Total Pattern Fitting to a Study of Crystallite Size and Strain in Zinc Oxide Powder
Authors: Langford J. I. , Louër D. , Sonneveld E. J. , Visser J. W.
Published: January 2013

A novel approach to the determination of crystallite size and lattice strain by means of Total Pattern Analysis is described. Parameters to define the position, magnitude, breadth and shape of individual peaks are obtained by an adaptation of the pattern fitting program of Sonneveld and Visser (J. Appl. Cryst. 8, 1–7, 1975). A rapid assessment of the nature of the specimen broadening is given by a Williamson-Hall Plot. This leads to a more detailed study of line breadths by, for example, Voigt analysis applied to several orders of reflections or to single lines. Preliminary results are given for the application of this procedure to ‘size only’ and ‘size-strain’ samples of ZnO.
A Mid-Century of Metallography—Retrospect and Aspect
Authors: Wyman L. L.
Published: January 2013

The following article by L. L. Wyman is reprinted from Fifty Years of Progress in Metallurgical Techniques, ASTM STP 430, 1968, contains information on the early role of ASTM Committee E-4 in the publication of the early Powder Diffraction File data cards and in the formation of the Joint Committee on Powder Diffraction Standards. In fact, Roy Wyman was probably the single most instrumental individual in obtaining the sponsorship by ASTM for the continued publication of the PDF up to 1969 when JCPDS became an independent corporation. Roy was on the Board of Directors of JCPDS from the time of its incorporation until his death in 1976. He was Treasurer of JCPDS from 1971 to 1974 and Chairman from 1974 to 1975. Committee E-4 is still active and is the Committee within ASTM which maintains Cooperative Society status with the JCPDS-ICDD.
An X-Ray Diffraction Analysis of the Patina of the Statue of Liberty
Authors: Matyi R. J. , Baboian R.
Published: January 2013

An X-ray powder diffraction analysis has been performed on several samples from the naturally occuring patina of the Statue of Liberty. This work, which was conducted as a service to the National Park Service as part of the restoration activities for the Statue, was performed to assess the impact of acid deposition on the phase composition of the patina. Samples of the patina that were obtained from various locations on the copper skin of the Statue were found to consist primarily of the basic copper sulfate known as brochantite or CuSO4·3Cu(OH)2. Another less stable form of basic copper sulfate CuSO4·2Cu(OH)2 known as antlerite was also observed in samples taken from areas that are more exposed to the incoming weather in New York harbor. The presence of antlerite supports the contention that acid deposition is promoting undesirable changes in the phase composition of the patina. Analyses were also performed on patina samples that were taken from pieces of the Statue's copper skin that had been removed in the years 1905 and 1980. X-ray powder diffraction of the corrosion product on the 1905 sample showed that it consisted primarily of the stable brochantite phase, while the 1980 sample displayed both copper chlorides as well as the less stable antlerite. Both samples also contained cuprite (Cu2O) which appears to have formed prior to either of the sulfates.
X-Ray Powder Data for Nissonite and Waylandite
Authors: Bayliss Peter
Published: January 2013

Complete X-ray powder data is recorded from type specimens of the minerals nissonite and waylandite. Debye-Scherrer films of 114.59 mm diameter were measured with an automated densitometer. A wide step width of 0.08°2θ was required, because the average reflection width at half height was 0.5°2θ. The 2θ positions and relative intensities of the reflections were calculated from a negative second derivative function based upon a five point curve.
Quantitative X-Ray Powder Diffraction Method Using the Full Diffraction Pattern
Authors: Smith Deane K. , Johnson Gerald G. , Scheible Alexandre , Wims Andrew M. , Johnson Jack L. , Ullmann Gregory
Published: January 2013

A new quantitative X-ray powder diffraction (QXRPD) method has been developed to analyze polyphase crystalline mixtures. The unique approach employed in this method is the utilization of the full diffraction pattern of a mixture and its reconstruction as a weighted sum of diffraction patterns of the component phases. To facilitate the use of the new method, menu-driven interactive computer programs with graphics have been developed for the VAX series of computers. The analyst builds a reference database of component diffraction patterns, corrects the patterns for background effects, and determines the appropriate reference intensity ratios. This database is used to calculate the weight fraction of each phase in a mixture by fitting its diffraction pattern with a least-squares best-fit weighted sum of selected database reference patterns.

The new QXRPD method was evaluated using oxides found in ceramics, corrosion products, and other materials encountered in the laboratory. Experimental procedures have been developed for sample preparation and data collection for reference samples and unknowns. Prepared mixtures have been used to demonstrate the very good results that can be obtained with this method.
On the Need for Users of the Powder Diffraction File to Update Regularly
Authors: Jenkins Ron , Holomany Mark , Wong-Ng Winnie
Published: January 2013

The International Centre for Diffraction Data has an ongoing program to ensure the quality of data in the Powder Diffraction File (PDF) reflects current requirements of the powder diffraction community. Annual updates are made available, comprising of around 1800 new patterns and 200 replacement patterns, but current statistics indicate that only about 20% of users of the PDF take advantage of these updates. This paper reviews changes which have been inplemented in the editorial review process to continuously monitor and review pattern quality and gives examples of better data which have resulted from these changes.
Deconvolution of Powder Diffraction Spectra
Authors: Wiedemann K. E. , Unnam J. , Clark R. K.
Published: January 2013

An improved deconvolution theory is presented for the resolution enhancement in powder diffraction spectra. In powder patterns, diffracted intensity, which is conceptually located at a single 2θ position, is actually distributed over a range of 2θ because of instrumental factors, crystal defects, beam penetration, and sample flatness. The location of the peak is usually taken as the peak maximum or the peak centroid. However, when interpreting complex spectra these approaches to locating peaks are not straightforward and deconvolution can be a useful tool. The method presented herein enhances resolution without altering peak area or peak position. Comparisons are made with results of other methods, with emphasis on deconvoluting spectra that contain random error. The discussion includes treatment of discrete data and analysis of the properties of the solution.
Standard X-Ray Diffraction Powder Patterns of Sixteen Ceramic Phases
Authors: Wong-Ng Winnie , McMurdie Howard F. , Paretzkin Boris , Zhang Yuming , Davis Katherine L. , Hubbard Camden R. , Dragoo Alan L. , Stewart James M.
Published: January 2013

The following sixteen reference patterns of boride, silicide, nitride and oxide ceramics represent the second group of reference patterns measured at the National Bureau of Standards under the project “High Quality Reference Patterns and Total Digital Powder Patterns of Technologically Important Ceramic Phases”. Included in the sixteen reference patterns are data for two high Tc superconducting oxide phases (CuSr0.2La1.8O4 and Ba2Cu3YO7) plus one related phase (BaCuY2O5). In addition to these new phases, five other patterns represent phases previously not contained in the PDF and eight represent major corrections to data in the file. The general methods of producing these X-ray powder diffraction reference patterns are described in this journal, Vol. 1, No. 1, pg. 40 (1986).
Profiles of CuKα Lines
Authors: Frevel Ludo K.
Published: January 2013

Accurate, digitized, spectral distribution data are given for CuKα radiation, comprising the profiles of CuKα1, CuKα2 and CuKα3,4. Three consistent analytical procedures are detailed for locating the peak of an X-ray emission line and are found to be superior to the conventional graphical centerline method.
Standard Reference Materials For X-Ray Diffraction Part II. Calibration Using d-Spacing Standards
Authors: Wong-Ng W. , Hubbard C. R.
Published: January 2013

External standard and internal standard calibrations are important procedures for achieving high accuracy in X-ray powder diffraction studies. The theoretical basis as well as procedures for obtaining calibration curves are given. Methods and examples of selecting Standard Reference Materials (SRMs) which are produced and issued by the National Bureau of Standards (NBS), and procedures of sample preparation with these standards are also described. Three examples are presented to indicate the value of using SRMs.
Powder Data for Metastable ZrxCe1−xO2 (x = 0.84 to 0.40) Solid Solutions with Tetragonal Symmetry
Authors: Meriani S. , Spinolo G.
Published: January 2013

Indexed powder patterns are reported for three homogeneous metastable ZrO2-CeO2 solid solution members with high-zirconia [(ZrO2)x mole fraction, x>.84 –.80] and lowzirconia (.60>x>.40) compositions. The primitive cell dimensions are: a = 3.6377(7) Å and c = 5.2394(11) Å at x = 0.84, and a = 3.7205(5) Å and c = 5.3039(7) Å at x = 0.5. Samples with intermediate compositions are heterogeneous. Also reported are powder data for the cubic (fluorite-structure) solution from a sample with x = 0.40 and a slightly different thermal history.
Reference X-Ray Diffraction Powder Patterns of Fifteen Ceramic Phases
Authors: Wong-Ng Winnie , McMurdie Howard F. , Paretzkin Boris , Zhang Yuming , Davis Katherine L. , Hubbard Camden R. , Dragoo Alan L. , Stewart James M.
Published: January 2013

Fifteen reference patterns of boride, silicide, selenide, telluride and oxide ceramics are reported. Included in the 15 reference patterns are data for three oxide phases which are related to high critical temperature (Tc) superconducting materials: BaCuO2, BaCuSm2O5and BaCuYb2O5. Four other patterns are included which represent phases previously not contained in the PDF. The remaining six are major corrections of data already included in the file. Reference data for phases Ba2CuY3O6.8and Ba2Y3CuO6appeared in the special July superconductor issue of theAdvanced Ceramic Materials, 1987. The general methods of producing these X-ray powder diffraction reference patterns are described in this journal, Vol. 1(1), 40 (1986).

Samples were mixed with one or two internal standards: silicon (SRM640a), silver, tungsten, or fluorophlogopite (SRM675). Expected 2θ values for these internal standards are specified in the methods described (ibid.). Data were measured with a computer controlled diffractometer. The POWDER-PATTERN system of computer programs was used to locate peak positions, to calibrate the patterns, and to perform variable indexing and least-squares cell refinement. A check on the overall internal consistency of the data was also provided by a computer program.
Computerization of the ICDD Powder Diffraction Database Critical Review of Sets 1 to 32
Authors: Wong-Ng Winnie , Hubbard Camden R. , Stalick Judith K. , Evans Eloise H.
Published: January 2013

The Powder Diffraction File of crystallographic data has been converted from printed data cards to a computer database. Extensive testing, review, and editing of the database were completed, the history and first stages of which are presented. Computer programs used to create and analyze the database are described.
An Hermetically Sealed Inert Atmosphere Cell for X-Ray Powder Diffraction
Authors: Ritter Joseph J.
Published: January 2013

The construction and use of a captive inert atmosphere cell for the preservation of atmospherically sensitive samples during X-ray diffraction is described.
Optimization of Stepsize in X-Ray Powder Diffractogram Collection
Authors: Cameron David G. , Armstrong Ernest E.
Published: January 2013

Fourier transform methods of smoothing and interpolation are applied to X-ray diffraction data. It is shown that, frequently, too small a step size is used. Major gains are to be expected by selection of the optimum step size and use of these methods.

A comparison of Fourier transforms of diffractograms of quartz measured between 67 and 69° 2θ, collected at varying step intervals (0.1 to 0.01° 2θ) was used to illustrate these applications. By examining the Fourier transform of the diffractogram and noting where it decays to die baseline, a reasonable estimate of the optimal step interval can be obtained. In addition, Fourier interpolation can be used to enhance the appearance of the diffractogram, approximating a continuous plot.
Standard X-Ray Diffraction Powder Patterns of Fifteen Ceramic Phases
Authors: Wong-Ng Winnie , McMurdie Howard F. , Paretzkin Boris , Zhang Yuming , Hubbard Camden R. , Dragoo Alan L. , Stewart James M.
Published: January 2013

Fifteen reference patterns of oxides, nitrides, borides, carbides, silicides, and sulfides are included in this report. The general methods of producing these X-ray powder diffraction reference patterns are described in this Journal, Vol. 1, No. 1, pg. 40(1986).

Samples were mixed with one or two internal standards: silicon (SRM640a), silver, tungsten, or fluorophlogopite (SRM675). Expected 2θ values for these internal standards are specified in the methods described (ibid.). Data were measured with a computer controlled diffractometer. The POWDER-PATTERN system of computer programs was used to locate peak positions, to calibrate the patterns, and to perform indexing and least-squares cell refinement. A check on the overall internal consistency of the data was also provided by a computer program.

Intensities were measured as peak heights above background and were read manually from strip charts. To minimize preferred orientation effects, the powders were passed through a 400 mesh sieve and were mixed with an amorphous diluent material, glass powder. Samples were prepared by side-drifting the mixture into the holder or by dusting a thin layer on a glass slide coated with a thin smear of silicone grease.

The support and interest of the ICDD in this project is gratefully acknowledged. The expert guidance of R. Roth of the Ceramics Division on material synthesis and the careful review of the manuscript by S. Block of the Ceramics Division and A. D. Mighell of the Reactor Division are fully appreciated. Acknowledgement is also extended to D. Minor for performing sample analysis by using SEM. In the production of these standard powder patterns, the ability to search NBS CRYSTAL DATA has proven invaluable.
X-Ray Powder Data for an Industrial Maghemite (γ-Fe2O3)
Authors: Schulz Douglas L. , McCarthy Gregory J.
Published: January 2013

X-ray powder data for a maghemite (γ-Fe2O3) used for computer hard disks is reported. This maghemite is cubic with space group P4132.
New Crystal Data for Seven Molybdates MIIUMo4O16 (MII = Mg,Mn,Cd,Ca,Hg,Sr,Pb)
Authors: Lee M.R. , Quartern M. , Jaulmes S.
Published: January 2013

Seven isotopic molybdates MIIUMo4O16 have been synthesized by solid state reaction with MII = Mg, Mn, Cd, Ca, Hg, Sr, Pb. Single crystals of CaUMo4O16 were obtained. Previously reported as triclinic, this compound is monoclinic, space group P2/n. Unit-cell parameters for the seven compounds are:

MgUMo4O16: a = 11.393(2), b = 6.505(1), c = 7.918(2) Å, β = 89.81(3)°, V = 586.8(5) Å3, Z = 2, Dx = 5.12 Mg m−3;

MnUMo4O16: a = 11.413(2), b = 6.555(1), c = 8.023(1) Å, β = 89.86(2)°, V = 600.2(4)Å3, Z = 2, Dx = 5.18 Mg m−3;

CdUMo4O16: a = 11.427(2), b = 6.607(1), c = 8.144(2) Å3, β = 90.40(2)°, V = 614.8(5)Å3, Z = 2, Dx = 5.37 Mg m−3;

CaUMo4O16: a = 11.443(3), b = 6.653(2), c = 8.239(2)Å, β = 90.51(3)°, V = 627.2(6)Å3, Z = 2, Dm = 4.83(5), Dx = 4.88 Mg m−3;

HgUMo4O16: a = 11.439(3), b = 6.643(1), c = 8.257(2)Å, β = 90.53(3)°, V = 627.4(6)Å3, Z = 2, Dx = 5.73 Mg m−3;

SrUMo4O16: 11.465(3), b = 6.768(2), c = 8.492(2) Å, β = 90.86(3)°, V = 658.8(6)Å3, Z = 2, Dx = 4.88 Mg m−3;

PbUMo4O16: a = 11.470(4), b = 6.813(2), c = 8.557(2)Å, β = 90.88(4)°, V = 668.7(8)Å3, Dx = 5.41 Mg m−3;

Powder diffraction data for each phase are reported.
Absolute Intensities - Outline of a Recommended Practice
Authors: de Woolf P.M. , Visser J.W.
Published: January 2013

The X-Ray Powder Data File (XRPDF) enables one to identify the compounds in a sample. More often than not, however, a semi-quantitative analysis is wanted. Visual inspection of the pattern may give a vague impression of the composition, but the errors of such a result are usually not within reasonable limits. Clearly a less subjective and more accurate method is wanted. If the necessary data are printed on the cards, such a method will greatly enlarge the usefulness of the File.
A Dynamic High Temperature XRPD Study of the Calcination of Zirconium Hydroxide
Authors: Mamott G. T. , Barnes P. , Tarling S. E. , Jones S. L. , Norman C. J.
Published: January 2013

Structural and chemical changes in materials can be dynamically observed by using time resolved X-ray Powder Diffraction (XRPD) to collect patterns as these events happen. During calcination of amorphous zirconium hydroxide, Zr(OH)4, and its crystallisation to a metastable tetragonal form of zirconia, ZrO2, patterns have been collected at 10°C temperature intervals during a heating sequence to 500°C. These patterns show both the onset of ordering within the amorphous starting material and the progress of its conversion into crystalline zirconia. Events are recorded within the pattern in the form of peak growth and reduction in amorphous component of the pattern with increasing temperature.
Standard X-Ray Diffraction Powder Patterns of Fourteen Ceramic Phases
Authors: Wong-Ng Winnie , McMurdie Howard F. , Paretzkin Boris , Kuchinski M. A. , Dragoo Alan L.
Published: January 2013

Fourteen reference patterns of oxide ceramics are reported. Included in the fourteen reference patterns are data for two high critical temperature superconducting oxide related phases (BaCuHo2O5 and Ba2YCu3O6.56). The general methods of producing these X-ray powder diffraction reference patterns were described previously in this journal (Vol. 1, No. 1, pg. 40 (1986)).
X-Ray Powder Diffraction Analysis of a Photoconductor Material p-Diethylaminobenzaldehyde Diphenylamine Hydrazone
Authors: Huang T. C. , Wang P. W.
Published: January 2013

A commercially available photoconductor material, p-diethylaminobenzaldehyde diphenylamine hydrazone, C23H25N3, has been purified and recrystallized from an absolute alcohol solution. The triclinic compound has been characterized by X-ray powder diffraction. Experimental 2θ values corrected for systematic errors, relative peak intensities, values of d, and the Miller indices of 74 observed reflections with 2θ up to 30.5° are reported. The powder diffraction data have been evaluated, and figures of merit are reported. Unit-cell parameters least-squares refined from the 74 observed reflections of the triclinic compound are in good agreement with those obtained from the single-crystal structure analysis.
X-Ray Diffraction Analysis of Barium-Strontium Sulfate (Barite-Celestite) Solid Solutions
Authors: Goldish Elihu
Published: January 2013

Crystal data are given for synthetic mixed bariumstrontium sulfates, and a powder pattern for (Ba0.50Sr0.50)SO4 is presented. Taken with previously published data for the end-member sulfates, we verify the nonlinear behavior of the unit-cell edges with composition, and present tables of interpolated data from which d-spacings for intermediate compositions can be calculated. The use of these data for analysis of complex natural samples by use of the 121 peak is described.
(Na0.5Bi0.5)TiO3: Synthesis and X-Ray Powder Diffraction Data
Authors: Zhou Fang , Xu Yue-ying , Li De-yu , He Chong-fang , Gao Ming , Wang Tian-bao
Published: January 2013

Crystallographic and X-ray powder diffraction data were derived from a sample of (Na0.5Bi0.5)TiO3 synthesized by standard ceramic techniques. The powder data were indexed on a monoclinic cell having the space group P2 or Pm, which differed from a previously reported rhombohedral cell.
X-Ray Powder Diffraction Data for Two Ammonium Copper Molybdates
Authors: Garin Jorge L. , Costamagna Juan A.
Published: January 2013

Two ammonium copper molybdates having the stoichiometric compositions (NH4)2Cu(MoO4)2(NH3)2 and (NH4)2Cu(MoO4)2 have been synthesized from aqueous solutions. The compounds crystallize in the triclinic system with space group . Crystal data and indexed X-ray powder diffraction data are reported for both phases.
Powder data for buckminsterfullerene, C60
Authors: McCready David E. , Alnajjar Mikhail S.
Published: January 2013

X-ray powder diffraction data for buckminsterfullerene, C60 are reported. The crystal structure is a face-centered cubic unit cell with a = 14.165 (1) Å. The reference intensity ratio (I/Icor) is 2.20.
Sm(OH)2NO3: Synthesis, characterization, powder diffraction data, and structure refinement by the Rietveld technique
Authors: Lengauer C. L. , Giester G. , Unfried P.
Published: January 2013

Sm(OH)2NO3, was prepared by hydrolysis of the corresponding nitrate, leading to a product which is insoluble in water. IR-spectroscopy showed a comparison with the analogous Gd-compound. The temperature of decomposition to SmONO3is below 573 K. The structure was refined by the Rietveld technique in space groupP21, (Z=2),a=6.3852(3) Å,b=3.7784(2) Å,c=7.7402(3) Å,β=97.572(3)°,V=185.11 Å3,Rp=4.9,Rwp=6.3,RB=4.0. The compound is isotypic with Ln(OH)2NO3(Ln=Pr,Nd,Gd). Infrared spectra and thermal decomposition data are also given for the Gd phase.
LCBASE: Program and database for phase identification
Authors: Paszkowicz W. , Makosa A.
Published: January 2013

A computer program for phase identification using powder diffraction data is presented. It works with a small database containing the unit-cell dimensions and Bravais lattice for chosen classes of inorganic substances. The algorithm works for single phase samples and such samples in which a single phase dominates. During the search, the peak positions generated using the reference unit cells are compared with the experimental ones. Unit-cell constants of all obtained solutions are (optionally) immediately refined. Application examples show that the method gives as possible solutions those database entries for which the cell dimensions differ from the investigated sample by not more than about 0.05 Å. These entries may include the true phase or isotypical phases unless the imposed chemical constraint does not exclude them. If the sample is a solid solution, then the algorithm is able to find phases of differing chemical composition belonging to the same solubility range (provided that the difference in lattice constants is not too large). One of the examples illustrates the possibility of application for electron-diffraction data.
Thermal expansion coefficients and Gruneisen parameters of quartz at high temperature by X-ray method
Authors: Rammo Nabil N. , Farid Saad B.
Published: January 2013

The temperature variation of the interplanar spacings (101), (112), and (211) of 325 mesh quartz was determined in the range 300–966 °K using X-ray powder diffractometry. The measured lattice parameters have been found to increase nonlinearly with temperature, and the dependence has been expressed by a polynomial of second degree from the least-squares fitting of the data, the results of which are presented herein. Values are given for the thermal expansion coefficients and Gruneisen parameter in the range 300 to 768 °K. In the range 768–966 °K, the expansion is zero. The derivatives dαa/dT, dαc/dT, and dαv/dT at ambient temperature are also given.
A standard test method for the determination of RIR values by x-ray diffraction
Authors: Schreiner Walter N.
Published: January 2013

The measurement of x-ray diffraction line intensities is the basis for quantitative phase analysis (see for example, Chung (1974), Davis (1986), and Hubbard and Snyder (1988)). While there are many sources of error in such measurements, in recent years computer automation of powder diffractometers and associated analytical software has made such measurements more practical and accurate. For example, profile fitting software has made it possible to determine integrated peak areas and to deconvolute overlapping lines. Another problem which affects quantitative analysis is the systematic error in instrument sensitivity as a function of 20 diffraction angle. This effect has been partially responsible for poor reproducibility of relative intensities between laboratories (Schreiner and Kimmel (1987), and Jenkins and Schreiner (1989)). But, because the error is systematic, corrections may be made by using a standard such as the National Institute of Standards and Technology SRM 1976 alumina plate (NIST 1991). These and other advances have led to a renewed interest in the determination of I/Ic (also called RIR - Reference Intensity Ratio) values for crystalline substances (e.g., Snyder (1992)). I/Ic is defined as the ratio of the intensity of the strongest line of an analyte to the corundum (113) line when the analyte is mixed 50:50 by weight with corundum. We present here a standard procedure used in our laboratory to experimentally measure I/Ic values, and which explicitly incorporates profile fitting and instrument sensitivity corrections. The procedure is written in the format of an ASTM (American Society for Testing and Materials) standard test method, however, inter-laboratory round robin tests have not been carried out to determine precision and bias associated with the method. While the method calls for corundum as the internal standard, another standard material, s, may be used, in which case the procedure will result in a ratio I/Is. Hubbard and Snyder (1988) have shown how to convert between I/Is and I/Ic. This method is based on the procedure routinely published in NBS Monograph 25 until 1986. It is augmented with corrections for the angularly dependent instrument sensitivity and with calculations of I/Ic for both variable and fixed divergence slit configurations. A Quattro Pro spreadsheet is used in our laboratory to do the calculations. An example of the spreadsheet is given in the appendix for one of two I/Ic runs of MgCO3. We also utilize the corundum in the I/Ic runs as an internal standard to determine displacement error corrections for preparation of digitized patterns of pure analyte phases. These patterns are submitted to the International Centre for Diffraction Data for inclusion in a whole pattern data file planned for some time in the future. The notation used here is the standard notation developed for the RIR method by Hubbard and Snyder (1988) and systematically extended by Snyder (1992). A table of the notation is given in the Terminology section below.
Multireflection RIR and intensity normalizations for quantitative analyses: Applications to feldspars and zeolites
Authors: Chipera Steve J. , Bish David L.
Published: January 2013

Quantitative determination of phase abundances using X-ray powder diffraction is a technique in wide use today. Of the various methods employed, the Chung, or RIR method, is one of the most common because it can provide reliable results for all sample types. However, improvements can be made to the Chung method of analysis for phases which exhibit large chemical or preferred orientation effects. These effects can often be accommodated by using intensity regions that encompass several reflections, by averaging intensities from nonparallel reflections, or by using RIR values that are allowed to vary based on a predetermined functional relationship. To accommodate the effects of preferred orientation and variable composition in feldspars, RIR values versus the intensity ratio between two peaks of feldspar standards mixed with corundum have been determined. Curves of RIR have been formulated for: (1) feldspar RIR13.0−14.0° versus the intensity ratio (13.0–14.0° 2θ intensity region/27.0–28.75° 2θ intensity region); (2) feldspar RIR23.6° peak versus the intensity ratio (23.6° 2θ peak/27.0–28.75° 2θ intensity region); and (3) clinoptilolite RIR020 versus (020 reflection/22.1–23.0° 2θ intensity region). For example, RIR values for the highly variable 13.0–14.0° 2θ region for feldspar can be improved such that the quantitative results produced has a standard deviation of only 15% instead of 53% using a fixed-average value. From these curves, improved RIR values can be obtained for the quantitative analysis of unknowns. Additionally, intensity ratios can be determined between two peaks of a phase so that given the intensity of one peak, the intensity of the other peak can be readily calculated. This allows for subtraction of the intensity of a peak from one phase overlapping a peak from a second phase which is to be used for quantitative analysis but which cannot be decomposed by profile fitting.