実験報告書様式（一般利用課題・成果公開利用）（ ※本報告書は英語で記述してください。ただし、産業利用課題として採択されている方は日本語で記述していただいても結構です。 ）Experimental Report
課題番号 Project No. 2012B0123

承認日 Date of Approval 2013/03/12
承認者 Approver Takashi Ohhara
提出日 Date of Report 2013/03/11
装置責任者 Name of Instrument scientist
Takashi Ohhara

実験課題名 Title of experiment

装置名 Name of Instrument/（BL No.）

Structural study of solid solution of M3H(XO4)2 protonic

SENJU/BL18

conductor

実施日 Date of Experiment
2012/12/9-2012/12/11

実験責任者名 Name of principal investigator

2013/2/6-2013/2/12

Ryoji Kiyanagi
所属 Affiliation
J-PARC JAEA
試料、実験方法、利用の結果得られた主なデータ、考察、結論等を、記述して下さい。（適宜、図表添付のこと）
Please report your samples, experimental method and results, discussion and conclusions. Please add figures andtables for better explanation.
1. 試料 Name of sample(s) and chemical formula, or compositions including physical form.
Solid Acid
Rb1-xKxH(SeO4)2 (x=0,1,2,3)

2. 実験方法及び結果 （実験がうまくいかなかった場合、その理由を記述してください。）
Experimental method and results.

If you failed to conduct experiment as planned, please describe reasons.

Four specimens with different x values were measured for structure
analyses. The samples were grown by evaporation method from watersolution. The sizes of single crystals obtained by this method highly
depended on the value of x. For the case of x = 0 and x = 3, rather large
single crystals were obtained typically 2x2x1 mm3 while for the other x only
smaller crystals were grown. The samples actually measured were about
2x2x1 mm3 for x=0 and 3, and 1x1x0.5 mm3. For the measurements thesample crystals were attached to vanadium pins with the diameter of 1.0 or0.5 mm and the pins were mounted on a RT goniometer available on BL18.

Fig. 1 The crystal ofRbK2H(SeO4)2

mountedon the RT goniometer.

2. 実験方法及び結果（つづき） Experimental method and results (continued)
All the measurements were conducted at room
temperature. Bragg intensities were collected with 31
two-dimensional scintillator detectors cylindricallysurrounding the sample chamber. Figure 2 shows atypical example of a Laue diffraction pattern observedfor one crystal orientation. In the measurements, 6different crystal orientations were measured with theFig. 2 Diffraction pattern from K3H(SeO4)2

exposure time of about 8 hours for each orientation.
The number of reflections observed for each sample
was several thousands.
Structure analyses were carried out using the observed intensity data that satisfy I/sigma > 3. The total
numbers of data actually used in the analyses were about 2000 while the number of the refined parameters
was 72 including anisotropic atomic displacement parameters for hydrogen atoms. The reliability factors
yielded after the refinement were typically 5%. The result for K3H(SeO4)2 is shown in Fig. 3 as anexample. As is seen in the figure, while most of the data show good consistency with the calculated values
from the model, some are significantly incompatible with the calculated ones. Although most probably this isdue to artifacts in the process of extracting the intensities, individual data have to be re-examined for furtheranalyses. Note that the data for the sample with x=1 has not been well analyzed yet. The reason might be thefact that the sample was the smallest and enough statistics might not have been obtained. Further attempts
to analyze the data are under way.
The lattice constants showed clear variation, namely shortening, upon the replacement of Rb with K
reflecting the difference of the ionic radii of the elements. The change is almost linear to the concentration ofK. This is in accordance with the preliminary results from X-ray powder diffraction data. The shortening of thehydrogen bond length, Roo, was also observed as a consequence of the shortening of the lattice parameters,
but the change was found not to be linear to the concentration of K. The detailed behavior will be revealed
once the x=1 data is analyzed. The variations of the concentrations of K on crystallographically different twosites are shown in Fig. 4. This result suggests that there is no preference for K in occupying either sites andthe difference merely arise from the difference in multiplicities of the sites.
140

1.0

120

Occupancy

Sample : K3H(SeO4)2
Data : 2074
Param. : 72
R = 5.17 %, wR = 4.89 %100Fo80
60
40

4e8f

0.8
0.6
0.4
0.2

Occupancies of K in Rb(3-x)K(x)H(SeO4)20.0

20

0.0

0.5

1.0

1.5

2.0

2.53.0x0020406080

100120140Fc

Fig. 3 Fo vs Fc plot of K3H(SeO4)2

Fig. 4 Variation of the occupancies of K in
Rb3-xKxH(SeO4)2