Phase Transitions and Water Dynamics of [Co(H20 )6](C104)2 and [Mn(H20 )6](BF4)2 Studied by Neutron Scattering Methods
نویسنده
چکیده
Inelastic incoherent neutron scattering (IINS) spectra and neutron powder diffraction (NPD) patterns, registered for [Co(H20 ) 6](C104)2 at 18 270 K and for [Mn(H20 )6](BF4)2 at 18 230 K, provided evidence that these crystals possess three solid phases in these ranges of temperatures. In both compounds the phase transition occurring at T C3 is connected with a change of the crystal structure, and that occurring at T C2 with a change in the rate of the reorientational motions of H20 ligands.
منابع مشابه
Phase Transitions in Crystalline
Solid polymorphism in five compounds of the type [Me(H20)6](BF4)2 , where Me = Mn, Fe, Co, Ni and Zn, have been studied in the temperature range 120 330 K by DSC. For each substance at least three solid modifications have been found. In addition, for compounds with Me = Mn, Fe and Zn some new low temperature phase transitions have been observed. The transition temperatures for the [Me(H20)6](BF...
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E. Mikuli, A. Migdał-Mikuli, I. Natkaniec', and J. Mayer Faculty of Chemistry of the Jagiellonian University, ulica Ingardena 3, 30-060 Krakow, Poland a Frank Laboratory of Neutron Physics, JINR, 141980 Dubna, Russia b H. Niewodniczanski Institute of Nuclear Physics, ulica Radzikowskiego 152, 31-342 Krakow, Poland Reprint requests to Dr. E. M.; Fax: (+4812) 634 05 15, E-mail: [email protected]...
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