Reference

Electric-field gradient at iodine-127 nuclei and geometry of iodate and hydrogen iodate groups in lithium iodate and hydrogen iodate crystals

Electric-field gradient at iodine-127 nuclei and geometry of iodate and hydrogen iodate groups in lithium iodate and hydrogen iodate crystals. Baisa, D. F.; Barabash, A. I.; Vertegel, I. G.; Vekhter, B. G.; Zenchenko, V. P.; Stavrov, S. S. (Inst. Fiz., Kiev, USSR). Khim. Fiz., 3(1), 18-24 (Russian) 1984. CODEN: KHFID9. DOCUMENT TYPE: Journal CA Section: 77 (Magnetic Phenomena) Section cross-reference(s): 65, 76 By the method of MO LCAO in the Mulliken-Wolfsberg-Helmholz approxn., a quantum mech. calcn. is performed of the electronic structure of the IO3- ions in crystals of a- and b-LiIO3. Parameters of NQR were calcd. also. The geometrical distortion of IO3- was estd. The obsd.There are some commonly used reagents with their cas registry numbers 13765-03-2 and 7782-68-5 in this article. magnitude and significant asymmetry h = 43.5% of the tensor of the elec.-field gradient at 127I in a-HIO3 can be explained only by taking into account the effect of a proton on the distribution of electron d. in HIO3. The increase in h in a-DIO3 is caused by lengthening of the O-D...D system and strengthening of the O-O bond. .

Effect of anharmonicity and vibration resonance interaction in the vibrational spectra of hydrogen-bonded crystals

Effect of anharmonicity and vibration resonance interaction in the vibrational spectra of hydrogen-bonded crystals. Gavrilko, T. A.; Puchkovskaya, G. A.; Yaremko, A.Chemicals with cas numbers 7782-68-5 and 1112-02-3 also play role. M. (Inst. Phys., Kiev 252650, USSR). J. Mol. Struct., 115, 99-102 (English) 1984. CODEN: JMOSB4. ISSN: 0022-2860. DOCUMENT TYPE: Journal CA Section: 73 (Optical, Electron, and Mass Spectroscopy and Other Related Properties) Absorption coeff. calcns. showed that strong optical and mech. anharmonicity of the OH group vibrations and the interaction between the main tone and the overtone of the other vibration of the same OH group and the same symmetry (Fermi resonance) lead to the formation of 2-phonon bound states (biphonons) seen in spectra as addnl. sharp bands. The IR and Raman bands halfwidth and shape of the main tone and the bound state were measured as a function of temp. and a possible theor. treatment was suggested. The anharmonicity parameters and low-frequency vibrations responsible for the temp. behavior of the main tone and of the biphonons were detd. .