Nanayakkara Sadisha, Tao Yunwen, Kraka Elfi
Computational and Theoretical Chemistry Group (CATCO), Department of Chemistry, Southern Methodist University, 3215 Daniel Avenue, Dallas, Texas 75275-0314, United States.
J Chem Theory Comput. 2022 Jan 11;18(1):562-579. doi: 10.1021/acs.jctc.1c00357. Epub 2021 Dec 20.
Local stretching force constants derived from periodic local vibrational modes at the vdW-DF2 density functional level have been employed to quantify the intrinsic hydrogen bond strength of 16 ice polymorphs, ices I, II, III, IV, V, VI, VII, VIII, IX, XI, XII, XIII, XIV, XV, XVII, and XIX, that are stable under ambient to elevated pressures. Based on this characterization on 1820 hydrogen bonds, relationships between local stretching force constants and structural parameters such as hydrogen bond length and angle were identified. Moreover, different bond strength distributions, from uniform to inhomogeneous, were observed for the 16 ices and could be explained in relation to different local structural elements within ices, that is, rings, that consist of different hydrogen bond types. In addition, criteria for the classification of hydrogen bonds as strong, intermediate, and weak were introduced. The latter was used to explore a different dimension of the water-ice phase diagram. These findings will provide important guidelines for assessing the credibility of new ice structures.
基于vdW-DF2密度泛函水平下周期性局域振动模式得出的局域拉伸力常数，已被用于量化16种冰多晶型物（冰I、II、III、IV、V、VI、VII、VIII、IX、XI、XII、XIII、XIV、XV、XVII和XIX）在环境压力至高压下稳定存在时的固有氢键强度。基于对1820个氢键的这一表征，确定了局域拉伸力常数与氢键长度和角度等结构参数之间的关系。此外，观察到16种冰的氢键强度分布从均匀到不均匀各不相同，并且可以根据冰中不同的局域结构单元（即由不同氢键类型组成的环）来解释。此外，还引入了将氢键分类为强、中、弱的标准。后者被用于探索水-冰相图的一个不同维度。这些发现将为评估新冰结构的可信度提供重要指导。
