bluuebunny/crossref_metadata_2025_split huggingface dataset:
Syntheses, Structures and Spectroscopic Properties of Mixed-Ligand Chromium(III) Complexes Containing 1,2-Bis(dimethylphosphino)ethane, 1,3-Bis(dimethylphosphino)propane or 1,1,1-Tris(dimethylphosphinomethyl)ethane
Authors: Suzuki Takayoshi , Kashiwabara Kazuo , Usami Tsutomu , Imamura Takeshi , Kiki Masakazu , Fujita Junnosuke , Kaizaki Sumio 
Published: September 2002

Abstract
Mixed-ligand chromium(III) complexes containing di- or tridentate phosphines, trans-[CrX2(dmpe)2]+ (X = Cl, Br, I, CN, NCS or N3; dmpe = Me2P(CH2)2PMe2), trans-[CrX′2(dmpp)2]+ (X′ = Cl, Br or I; dmpp = Me2P(CH2)3PMe2), [CrX′′3(tdmme)] (X′′ = Cl, Br, CN or NCS; tdmme = MeC(CH2PMe2)3) and [CrCl2(tdmme)(PMe3)]+, have been prepared and their structures and spectroscopic properties have been investigated. The single-crystal X-ray analyses of trans-[CrI2(dmpp)2]I (6) and [Cr(CN)3(tdmme)]·2H2O (16·2H2O) have also been reported. The Cr–P bond length in 6 (2.5147(6) Å) is longer than those in trans-[CrCl2(dmpe)2]BPh4 (av 2.445 Å) and in 16·2H2O (av 2.455 Å). In the UV-vis absorption spectra of trans-[Cr(Cl or Br)2(dmpe or dmpp)2]+, an intense (ε &gt; 1000 dm3 mol−1 cm−1) absorption envelope is observed at 20000–30000 cm−1, in addition to the 4B1 → a4E d–d transition band at ∼17000 cm−1 (ε = 44–65 dm3 mol−1 cm−1). The envelope consists of three d–d transition components: 4B1 → 4A2, 4B2 and b4E, similar to the corresponding H2N(CH2)2NH2 (= en) complexes. The magnetic circular dichroism (MCD) spectra of these didentate phosphine complexes show a spin-forbidden d–d transition (4B1 → 2E, 2B2) component at ∼19000 cm−1. The ligand-field and Racah parameters, Δ(d), Δ(e), Δ(t2) and B, of the complexes are estimated. It is found that the ligand-field and repulsion parameters of the dmpp complexes are almost the same as those of the corresponding en complexes. For the dmpe complexes, while Δ(d) is just slightly smaller than those of the dmpp and en complexes, the tetragonal symmetry parameters, Δ(e) and Δ(t2), are much reduced. The ligand-field perturbation energies of phosphines are estimated as Δdmpp = 21830 &gt; Δtdmme = 20920 &gt; Δdmpe = 20620 cm−1, the order of which is strange, since the Cr–P bond lengths in the complexes increase in the order of dmpp &gt; tdmme &gt; dmpe. Furthermore, the interelectronic repulsion parameter B of [Cr(Cl or Br)3(tdmme)] estimated from the 4A2 → 4T1 transition energy (B35) is remarkably much smaller than the parameter estimated from the spin-forbidden 4A2 → 2T2 transition energy (B55).
Structural Effects on Nitratocopper(II) Complexes of Tris(pyrazolyl)borates
Authors: Fujisawa Kiyoshi , Miyashita Yoshitaro , Yamada Yasunori , Okamoto Ken-ichi 
Published: September 2002

Abstract
Some structural influences on nitratocopper(II) complexes ligated by a series of hydrotris(pyrazolyl)borates are described. The 5-position of pyrazole rings as well as the 3-position is important to provide coordination structure.
Preparation of Artificial Urushi via an Environmentally Benign Process
Authors: Ikeda Ryohei , Tanaka Hozumi , Oyabu Hiroshi , Uyama Hiroshi , Kobayashi Shiro 
Published: September 2002

Abstract
“Artificial urushi” has been developed by laccase-catalyzed curing of new urushiol analogues. The analogues were designed and conveniently synthesized by regioselective acylation of phenol derivatives having a primary alcohol with unsaturated fatty acids using lipase as catalyst. The curing of the catechol derivative having a linolenoyl group proceeded in the presence of acetone powder from Chinese urushi, yielding the crosslinked film (“artificial urushi”) with high hardness and gloss surface, which are comparable with those of natural urushi coating. The analogues obtained from vanillyl alcohol were also cured. FT-IR monitoring of the curing showed that the crosslinking mechanism was similar to that of the natural urushi. The curing of the urushiol analogues in the presence of starch–urea phosphate took place to give the artificial urushi consisting exclusively of synthetic compounds.
Calf-Thymus DNA Interaction with Cr(III)-Gallate and Cr(III)-Ethyl Gallate Studied by FTIR Spectroscopy and Capillary Electrophoresis
Authors: Arakawa Hirohumi , Watanabe Norimoto , Tajmir-Riahi Heidar-Ali 
Published: September 2002

Abstract
Cr(VI) salts are well known to be carcinogen, and are reduced by various cellular components to form cross-linked Cr(III) products. Organic compounds, such as gallic acid (GA) and ethyl gallate (EGA), reduce Cr(VI) to Cr(III) to form Cr(III)-gallate [Cr(III)-GA] and Cr(III)-ethyl gallate [Cr(III)-EGA] as final products. These Cr(III)-tannin complexes are DNA binders. The interaction of calf-thymus DNA with Cr(III)-GA and Cr(III)-EGA in aqueous solutions at physiological pH were studied at Cr(III)/DNA (phosphate) molar ratios (r) of 1 : 160, 1 : 80, 1 : 40, 1 : 20, 1 : 10, 1 : 4, and 1 : 2 using FTIR spectroscopy and capillary electrophoresis. An analysis by FTIR showed that at low concentrations (r = 1/80 and 1/40), Cr(III)-GA and Cr(III)–EGA mainly bind to the guanine N-7 atom of the G–C base pairs with minor perturbations of the A–T base pairs. At r &gt; 1/20, a partial helix opening occurred with major perturbations of the G–C and A–T base pairs. At r &gt; 1/10, aggregation of the Cr(III)-tannin–DNA complexes occurred. However, no DNA conformational changes were observed, and the DNA maintained the B-family structure. The binding constants of the Cr(III)-GA–DNA and Cr(III)-EGA–DNA were estimated to be 3.8 × 104 M−1 and 6.2 × 104 M−1, respectively, by Scatchard plots following capillary electrophoresis. These results suggest that the Cr(III)-tannin complexes are external DNA binders, and do not form a chelate with the DNA.
Hydrophobic Character of Ca2+-bound S-100 Complexes
Authors: Matsuda Sadayuki 
Published: September 2002

Abstract
The hydrophobic character of S-100 complexes was investigated in terms of their adsorbability on phenyl-Sepharose gel in the presence of several co-adsorptive reagents. The following results were obtained: The hydrophobicity of S-100a.a′ was obviously increased by Ca2+-binding, and that of Ca2+-bound S-100a.a′ had practically no further increase upon mastoparan (MP)- or Zn2+-binding. In the case of S-100b, on the contrary, the increase in the hydrophobicity by Ca2+-binding was less than that for the former, and that of the Ca2+-bound sample showed a further increase by MP-binding, or especially by Zn2+-binding.
The hydrophobicity was also investigated with 2-p-toluidinonaphthalene-6-sulfonate (TNS). The adsorbability of the TNS-bound area was evaluated using fluorescence spectrophotometry. The hydrophobicity of Ca2+-bound S-100a.a′ was enhanced only by MP-binding. In the case of Ca2+-bound S-100b, both MP- and Zn2+-binding had appreciable effects on the hydrophobicity, and their co-existence had a greater effect than the additive of each one.
Solvolytic Stereoselective Debromination of vic-Dibromides with HMPA
Authors: Khurana Jitender Mohan , Bansal Geeti , Chauhan Sushma 
Published: September 2002

Abstract
A simple and efficient procedure for the debromination of vic-dibromides has been reported with hexamethylphosphoric triamide at 155–160 °C under a nitrogen atmosphere without the aid of any reagent.
Structure and Properties of 9-(Cycloheptatrienylidene)fluorene and Its Derivatives
Authors: Minabe Masahiro , Tomiyama Takashi , Nozawa Toshiya , Noguchi Makoto , Nakao Akiko , Oba Toru , Kimura Takao 
Published: September 2002

Abstract
One sesquifulvalene, 9-(cycloheptatrienylidene)fluorene, was found to be composed of a flat fluorenylidene part and a non-planar cycloheptatrienylidene moiety. 1-Substituted 9-(cycloheptatrienylidene)fluorene was not obtained because of a steric repulsion between the 1-substituent and the 7′-hydrogen of the seven-membered ring. Upon consideration of their 13C NMR spectra, the electronic properties of the seven-membered ring are slightly influenced by introducing a substituent (halogen, methoxy group, etc.) on the fluorenylidene part. The dissolution of 9-(cycloheptatrienylidene)fluorene in trifluoroacetic acid–chloroform afforded the (9-fluorenyl)tropylium cation. The substituent attached to the fluorene part also slightly influences the tropylium moiety.
Theoretical CD Spectrum Evaluation of the Indolylfulgide Molecules by Using Semi-Empirical Molecular Orbital Calculations
Authors: Ankai Eikoh , Sakakibara Kazuhisa , Uchida Soichi , Uchida Yuki , Yokoyama Yayoi , Yokoyama Yasushi 
Published: September 2002

Abstract
A fulgide is a photochromic molecule which can not be isomerized by a thermal reaction. The CD spectra of the optically resolved helically chiral indolylfulgide (99% enantiomer excess), whose absolute configurations have been determined by an X-ray crystallographic analysis of their binaphthyl derivative, were estimated theoretically within the framework of semi-empirical molecular-orbital calculations. The optical rotatory strength of the indolylfulgide was calculated based on the Rosenfeld equation by using the optimized structures, conformational energies, and molecular orbitals. The estimated CD spectra reproduced characteristic features, such as the peak shape and sign of the Cotton effect, quite well, though the accuracy of the calculated wavelengths for the individual CD peaks’ maxima was fair.
Synthesis of Pyrrolo[1,2-a]quinoxaline Derivatives by Lewis Acid-Catalyzed Reactions of 1-(2-Isocyanophenyl)pyrroles
Authors: Kobayashi Kazuhiro , Irisawa Susumu , Matoba Takeshi , Matsumoto Takashi , Yoneda Keiichi , Morikawa Osamu , Konishi Hisatoshi 
Published: September 2002

Abstract
1-(2-Isocyanophenyl)pyrroles have been prepared. They react in moderate to good isolated yields with aldehydes (or ketones), oxiranes, and acetals in the presence of catalytic amounts of diethyl ether–boron trifluoride to give pyrrolo[1,2-a]quinoxalines carrying an oxyalkyl substituent, such as α-hydroxyalkyl, β-hydroxyalkyl, or α-alkoxyalkyl, at the 4-position.
Stereocontrol in a Ytterbium Triflate-Catalyzed 1,3-Dipolar Cycloaddition Reaction of Carbonyl Ylide with N-Substituted Maleimides and Dimethyl Fumarate
Authors: Suga Hiroyuki , Kakehi Akikazu , Ito Suketaka , Inoue Kei , Ishida Hajime , Ibata Toshikazu 
Published: September 2002

Abstract
The addition of Yb(OTf)3 (10 mol%) in a Rh2(OAc)4-catalyzed reaction of o-(methoxycarbonyl)-α-diazoacetophenone with N-methylmaleimide in CH2Cl2 or in diethyl ether gave cycloadducts with high endo-selectivity (endo : exo = 95 : 5–96 : 4). The CuOTf (20 mol%)- or CuCl-Yb(OTf)3 (5 mol%)-catalyzed reaction also gave 1,3-dipolar cycloadducts in an endo-selective manner (endo : exo = 94 : 6). On the other hand, a reaction using only Rh2(OAc)4 (5 mol%) as the catalyst in benzene under reflux gave cycloadducts with exo-selectivity (endo : exo = 11 : 89). The reaction of N-ethyl- and N-phenylmaleimides under the same conditions showed a similar tendency in terms of the stereoselectivity.
Chemoenzymatic Synthesis of a Trisaccharide–Serine Conjugate, Gal(β1-3)Gal(β1-4)Xyl(β1-O)–l-Ser, Use of Galactosyl Fluoride as a Donor for Transglycosylation
Authors: Fukase Koichi , Yasukochi Takashi , Kusumoto Shoichi 
Published: September 2002

Abstract
The trisaccharide–serine conjugate [Gal(β1-3)Gal(β1-4)Xyl(β)-Ser], constituting the linkage region between the glycosaminoglycan and protein in proteoglycan, was synthesized by using enzymatic transglycosylation with a β-d-galactosidase as a key reaction. The yields of transglycosylation were much improved by using galactosyl fluoride as a donor in comparison with those obtained by a conventional p-nitrophenyl (PNP) galactoside. After enzymatic synthesis of Gal(β1-3)Gal(β1-4)Xyl(β)–PNP, cleavage of the PNP group of the fully acetylated trisaccharide, chemical coupling with serine, and final deprotection afforded Gal(β1-3)Gal(β1-4)Xyl(β)–Ser.
Asymmetric Addition of Allylic Stannanes to Aldehydes Catalyzed by BINAP•Ag(I) Complex
Authors: Yanagisawa Akira , Nakashima Hiroshi , Nakatsuka Yoshinari , Ishiba Atsushi , Yamamoto Hisashi 
Published: September 2002

Abstract
Catalytic asymmetric allylation of aldehydes with allylic trialkylstannanes was achieved with BINAP•AgOTf complex as catalyst. The chiral silver(I) catalyst was readily prepared by stirring an equimolar mixture of BINAP and silver(I) triflate in THF at room temperature. The allylation of a variety of aromatic and α,β-unsaturated aldehydes resulted in high yields and remarkable enantioselectivities. Addition of γ-substituted allylstannanes such as 2-butenyltributylstannane and trialkyl-2,4-pentadienylstannanes exclusively gave γ-adducts. High anti-selectivity was also obtained in the reaction with 2-butenyltributylstannane, irrespective of the configuration at the double bond.
An Effective Method for the Preparation of Chiral Polyoxy 8-Membered Ring Enone Corresponding to the B Ring of Taxol
Authors: Shiina Isamu , Shibata Jun , Ibuka Ryoutarou , Imai Yumiko , Mukaiyama Teruaki 
Published: September 2002

Abstract
An effective method for the preparation of 8-membered ring enone, (4S,5R,7R,8R)-4,8-bis(benzyloxy)-7-(t-butyldimethylsiloxy)-5-(4-methoxybenzyloxy)-2,6,6-trimethylcyclooct-2-enone (1), in sufficient quantities was developed. Optically active trioxy aldehyde, (3R,4S)-4-benzyloxy-5-(t-butyldimethylsiloxy)-3-(4-methoxybenzyloxy)-2,2-dimethylpentanal (3), was prepared first by diastereoselective dihydroxylation of (2R,4S)-2-(4-methoxyphenyl)-5,5-dimethyl-4-vinyl-1,3-dioxane derived from D-pantolactone. Next, 8-chloro-7-oxoaldehyde, (2R,3R,5R,6R)-2,6-bis(benzyloxy)-5-(t-butyldimethylsiloxy)-8-chloro-3-(4-methoxybenzyloxy)-4,4-dimethyl-7-oxononanal (30), was newly synthesized by the following reactions: i) MgBr2•OEt2-mediated diastereoselective aldol reaction of the aldehyde 3 with (Z)-2-benzyloxy-1-methoxy-1-(trimethylsiloxy)ethene and ii) reaction of methyl (2R,3R,5R,6S)-2,6-bis(benzyloxy)-3,7-bis(t-butyldimethylsiloxy)-5-(4-methoxybenzyloxy)-4,4-dimethylheptanoate with 1,1-dichloroethyllithium, followed by successive reductive dehalogenation of thus formed 1,1-dichloroethyl ketone with 1,1-dichloroethyllithium. Then, the chiral 8-chloro-7-oxoaldehyde 30 was converted to the 8-membered ring enone 1 by SmI2-mediated aldol cyclization.
Conformational Study of the Tandem Repeat Sequence in RNA Polymerase II by Circular Dichroism Spectroscopy
Authors: Ohiso Isao , Tsunemi Masahiko , Zhao Budiao , Nishi Norio 
Published: September 2002

Abstract
The largest subunit of RNA polymerase II has an interesting C-terminal domain, which consists of a multiple tandem repeat of a heptapeptide with the consensus sequence Ser–Pro–Thr–Ser–Pro–Ser–Tyr. However, the functional role of this sequence is unclear. One might assume that the conformation of the tandem repeat is very important for its function. The conformation of poly(Ser–Pro–Thr–Ser–Pro–Ser–Tyr) and H–Ser–Pro–Thr–Ser–Pro–Ser–Tyr–OH, corresponding to the repeat and the repeating unit of the C-terminal domain, respectively, were investigated exhaustively by circular dichroism (CD). The CD spectrum of H–Ser–Pro–Thr–Ser–Pro–Ser–Tyr–OH indicated the presence of a turn structure in water, which was further stabilized in 2,2,2-trifluoroethanol (TFE) and in acetonitrile. The CD spectra of the polyheptapeptide poly(Ser–Pro–Thr–Ser–Pro–Ser–Tyr) suggested that the disordered conformation was predominant in water and that the turn structure was stabilized by increasing the content of TFE or acetonitrile in the solvent. We suggest that the polyheptapeptide forms not only a turn structure at the heptapeptide unit Ser–Pro–Thr–Ser–Pro–Ser–Tyr, but also a kind of super conformation induced by the periodicity of the sequence in TFE or acetonitrile.
Catalytic Activity of Lanthanide(III) Ions for the Dehydration of Hexose to 5-Hydroxymethyl-2-furaldehyde in Water
Authors: Seri Kei-ichi , Inoue Yoshihisa , Ishida Hitoshi 
Published: September 2002

Abstract
All of the lanthanide(III) (La3+–Lu3+) efficiently catalyzed the dehydration of hexose in water at 140 °C to produce 5-hydroxymethyl-2-furaldehyde (HMF) without accompanying further hydrolysis to levulinic acid, which is routinely obtained as a by-product in the conventional Brønsted acid-catalyzed reactions. The relationships between the catalytic activity and the ionic radius (ri) of lanthanides(III) for the dehydration of d-fructose and d-glucose were found to have a double-peak profile maximizing at Pr or Nd (ri 1.00 Å) and Er or Yb (ri 0.87 Å) with a dip at Sm (ri 0.96 Å). Kinetic analyses revealed that the rate-determining step is not the complex formation of lanthanide(III) ion with the saccharide molecule, but a subsequent reaction from the substrate-catalyst complex. Possible reasons why the catalytic activity–ionic radius relationships show a two-peak profile are discussed.
Increasing the Selectivity of Bromination of Aromatic Compounds Using Br2/SiO2
Authors: Ghiaci M , Asghari J 
Published: September 2002

Abstract
In the presence of silica, a number of aromatic hydrocarbons such as toluene, o-, m-, and p-xylene, anthracene and phenol are brominated by Br2 under mild conditions; for example Br2/SiO2 brominates naphthalene readily at 25 °C to 1-bromonaphthalene. For comparison, we have also brominated all of the substrates in with bromine in the absence of silica gel.
Preparation of a Kaolinite–Nylon 6 Intercalation Compound
Authors: Matsumura Asako , Komori Yoshihiko , Itagaki Tetsuro , Sugahara Yoshiyuki , Kuroda Kazuyuki 
Published: September 2002

Abstract
A kaolinite–nylon 6 intercalation compound was prepared by the polymerization of 6-aminohexanoic acid (AHA) in the interlayer space of kaolinite. The intercalation of AHA was achieved by a guest displacement reaction using a kaolinite–methanol intercalation compound as an intermediate. After AHA dissolved in a mixed solvent of methanol and water (1 : 3) was added to a kaolinite–methanol intercalation compound, the mixture was stirred for 3 h. The basal spacing of the product increased to 1.23 nm, indicating the intercalation of AHA molecules with a monolayer arrangement between the layers of kaolinite. AHA was polymerized by a heat treatment at 250 °C for 1 h under a nitrogen flow. Although the basal spacing of the heat-treated product slightly decreased to 1.16 nm, the spacing was larger than those of kaolinite and the kaolinite–methanol intermediate. The formation of a kaolinite-nylon 6 intercalation compound was confirmed by the appearance of IR bands due to amide I (1637 cm−1) and amide II (1550 cm−1).
Pyrene Chemisorption Film on an Alumina Plate as an Optical Oxygen-Sensing Material
Authors: Amao Yutaka , Okura Ichiro , Miyashita Tokuji 
Published: September 2002

Abstract
An optical oxygen sensor based on the fluorescence quenching of pyrene-1-butyric acid (PBA) chemisorption film onto an alumina plate was developed. The fluorescence intensity of PBA film decreased with increasing oxygen concentration. The PBA film sensor is calibrated by a modified Stern–Volmer equation.
Inhibition of NO Decomposition Activity of Perovskite-type Oxides by Coexisting Carbon Dioxide
Authors: Teraoka Yasutake , Torigoshi Ken’ichiro , Kagawa Shuichi 
Published: September 2002

Abstract
Catalytic activity of La-based perovskites, La0.8Sr0.2CoO3 as a representative example, for the direct NO decomposition above 500 °C was decreased by the coexistence of gaseous carbon dioxide. The effect of carbon dioxide was more severe than the well-known impact of oxygen, though it was reversible at 800 °C.
UV and Visible Emission Spectra from the Photodissociation of Carbonyl Sulfide Using Synchrotron Radiation at 15–30 eV
Authors: Mitsuke Koichiro , Mizutani Masakazu 
Published: September 2002

Abstract
The photofragmentation of OCS at photon energies of 15–30 eV has been studied by dispersed fluorescence spectroscopy. The primary photon beam was monochromatized undulator radiation supplied from the UVSOR facility. The following emission-band systems have been identified: OCS+[A2ΠΩ(0,0,0) → X2ΠΩ(0,0,v3′′)], CO+(A2ΠΩ → X2Σ+), CS+(B2Σ+ → A2ΠΩ), and CO(d3Δ → a3Π). All of the transitions, except for OCS+[A2ΠΩ → X2ΠΩ], were first observed in the vacuum UV photodissociation of OCS. The fluorescence excitation spectra for the OCS+[A2ΠΩ(0,0,0) → X2ΠΩ(0,0,v3′′)] and CS+(B2Σ+ → A2ΠΩ) transitions were measured in the photon energy range of 15.1–15.75 and 21.8–26 eV, respectively. The emission spectra obtained at 20.85 and 22.9 eV exhibit atomic transitions of S[nd3Do → 4p3Pe (n = 6–9)], which result from the neutral dissociation of superexcited Rydberg states of OCS into S(nd3Do) + CO. Possible excited states of the counterpart CO are discussed on the basis of the difference in the n distribution between the two spectra.
Time Resolved ESR Study on the Photochemical Reactions of Pyrene and Nitroxide Radical System in Micelle; Formation of Spin-Correlated Pyrene Cation–Nitroxide Pairs
Authors: Kawai Akio , Shikama Atsushi , Mitsui Masaaki , Obi Kinichi 
Published: September 2002

Abstract
Time-resolved ESR (TR-ESR) spectra were measured in the laser excitation of aromatic compounds such as xanthone, bromopyrene, fluoranthene (Flt) and pyrene (Py) in sodium dodecyl sulfate (SDS) aqueous micellar system in the presence of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO). Net emission (Em) signals of triplet hyperfine (hf) lines of TEMPO were observed in xanthone– and bromopyrene–TEMPO systems. The chemically induced dynamic electron polarization (CIDEP) was explained by radical-triplet pair mechanism. Antiphase signals of TEMPO with Em in low-field side and enhanced absorption in high-field side (EA) of each triplet hf line were superimposed on net Em signals in Flt– and Py–TEMPO systems. The square laser power dependence of the EA signal suggests that the two-photon ionization of Flt and Py is related to the EA antiphase signal. Rate constants of the reactions occurring in SDS solution were determined by analysis of transient absorption decays in the Py–TEMPO system. The reaction rates of Py+–TEMPO and 3Py*–TEMPO in SDS solution were determined as 1.2 × 106 s−1 and 3.0 × 105 s−1, respectively, at the TEMPO concentration of 2 mM (M = mol dm−3). According to these measurements, it was concluded that the EA CIDEP is due to spin-correlated radical pair (SCRP) of TEMPO and Py+ which was formed in the electron transfer reaction from TEMPO to Py+. Simulation of TR-ESR spectra was carried out using SCRP theory. From kinetic analysis of intermediates together with the simulation of TR-ESR spectra, it was concluded that both SCRP of Py+–TEMPO and RTPM of 3Py*–TEMPO contribute to the CIDEP of TEMPO.
Pressure- and Temperature-Induced Phase Transitions in 2,4,6-Trichloro-1,3,5-triazine Crystal
Authors: Tanaka Makiko , Kariu Chinatu , Suzuki Yoshio , Nibu Yoshinori , Shimada Ryoichi , Shimada Hiroko 
Published: September 2002

Abstract
The effects of pressure and temperature on the frequencies and band structures of the Raman active inter- and intramolecular vibrations of 2,4,6-trichloro-1,3,5-triazine crystal were studied. The changes in the Raman frequency, band width, and band structure of both the inter- and intramolecular vibrations induced by changes of pressure and temperature indicate that (1) a displacive phase transition caused by a shear distortion of π-stacked layer structure may take place under about 1.7 GPa at 298 K and (2) the intermolecular nitrogen–chlorine donor–acceptor attractive interactions supporting the extensive network structure in crystal have a direct effect upon the totally symmetric C–Cl stretching vibration.
Heat Capacity and Glass Transition of Crystalline Pentachloronitrobenzene
Authors: Tan Zhi-Cheng , Nakazawa Yasuhiro , Saito Kazuya , Sorai Michio 
Published: September 2002

Abstract
The heat capacity of crystalline pentachloronitrobenzene was measured by adiabatic calorimetry between 6 and 303 K. A large step in heat capacity was detected around 185 K; this is attributed to a glass transition corresponding to freezing of structural disorder. The observed glass transition temperature was similar to that estimated from the temperature dependence of the dielectric relaxation due to molecular reorientation around the “sixfold axis” of the benzene core.