کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1404198 | 1501883 | 2008 | 4 صفحه PDF | دانلود رایگان |
On the examples of the K3(H/D)(SO4)2 family (I), the derivatives of 9-hydroxyphenalenone (II) and chromous acids α-(H/D)CrO2 (III) the problem of the deuteration-induced structural phase transition (SPT) is considered using pseudospin dynamic Ising model formalism. The pseudospin Hamiltonian parameters – tunneling integrals Ω(H/D) and Ising model coupling parameters Jij(H/D) along with molecular field parameters J0(H/D) have been evaluated on the base of quantum chemical models and various computational techniques. The crystal-chemistry factors that influence on the values of these parameters are discussed. For I and II solids zero-dimensional character of the H-bond network is believed to be the main reason of the deuteration-induced SPT, although the pronounced geometrical (H/D) isotope effect (0.04 Å) also may play a noticeable role for I. Meanwhile for III such SPT is due to the giant (0.1 Å) geometrical (H/D) isotope effect.
Journal: Journal of Molecular Structure - Volume 880, Issues 1–3, 27 May 2008, Pages 44–47