Singer Sherwin J, Kuo Jer-Lai, Hirsch Tomas K, Knight Chris, Ojamäe Lars, Klein Michael L
Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA.
Phys Rev Lett. 2005 Apr 8;94(13):135701. doi: 10.1103/PhysRevLett.94.135701. Epub 2005 Apr 7.
The existence of an ice Ih/XI proton-ordering transition to a low-temperature ferroelectric phase has sparked considerable debate in the literature. Electronic density functional theory calculations, extended using graph invariants, confirm that a transition to a low-temperature ferroelectric phase should occur. The predicted transition at 98 K is in qualitative agreement with the observed transition at 72 K, and the low-temperature phase is the ferroelectric phase determined in diffraction experiments. The theoretical methods used to predict the phase transition are validated by comparing their prediction to the well-characterized ice VII/VIII proton-ordering transition.
冰Ih/XI质子有序转变为低温铁电相的存在在文献中引发了相当多的争论。利用图不变量扩展的电子密度泛函理论计算证实，应该会发生向低温铁电相的转变。预测的98K转变与观察到的72K转变在定性上一致，并且低温相是在衍射实验中确定的铁电相。通过将预测结果与特征明确的冰VII/VIII质子有序转变进行比较，验证了用于预测相变的理论方法。
