Garrote-Márquez Alejandro, Lodeiro Lucas, Hernández Norge Cruz, Liang Xia, Walsh Aron, Menéndez-Proupin Eduardo
Departamento de Física Aplicada I, Escuela Politécnica Superior, Universidad de Sevilla, Seville E-41011, Spain.
Departamento de Química, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa 7800003, Santiago Chile.
J Phys Chem C Nanomater Interfaces. 2024 Nov 26;128(49):20947-20956. doi: 10.1021/acs.jpcc.4c04686. eCollection 2024 Dec 12.
The structures and properties of organic-inorganic perovskites are influenced by the hydrogen bonding between the organic cations and the inorganic octahedral networks. This study explores the dynamics of hydrogen bonds in CHNHPbBr across a temperature range from 70 to 350 K, using molecular dynamics simulations with machine-learning force fields. The results indicate that the lifetime of hydrogen bonds decreases with increasing temperature from 7.6 ps (70 K) to 0.16 ps (350 K), exhibiting Arrhenius-type behavior. The geometric conditions for hydrogen bonding, which include bond lengths and angles, maintain consistency across the full temperature range. The relevance of hydrogen bonds for the vibrational states of the material is also evidenced through a detailed analysis of the vibrational power spectra, demonstrating their significant effect on the physical properties for this class of perovskites.
有机-无机钙钛矿的结构和性质受有机阳离子与无机八面体网络之间氢键的影响。本研究使用机器学习力场的分子动力学模拟，探索了CHNHPbBr在70至350 K温度范围内氢键的动力学。结果表明，氢键的寿命随温度升高从7.6 ps（70 K）降至0.16 ps（350 K），呈现出阿伦尼乌斯型行为。氢键的几何条件，包括键长和键角，在整个温度范围内保持一致。通过对振动功率谱的详细分析，也证明了氢键与材料振动状态的相关性，表明它们对这类钙钛矿的物理性质有显著影响。
