Korabel'nikov Dmitry V, Fedorov Igor A
Kemerovo State University, Krasnaya 6, Kemerovo, 650000, Russia.
Phys Chem Chem Phys. 2025 Jan 22;27(4):2232-2239. doi: 10.1039/d4cp03913k.
The compressibility of crystalline tetrabromophthalic anhydride (TBPA) and 1-ethyl-3-methylimidazolium nitrate (EMN) was studied based on density functional theory including dispersion interactions at pressures below 1 GPa. It is found for the first time that EMN demonstrates negative linear compressibility (NLC) up to ∼0.15 GPa, whereas TBPA shows significant NLC at pressures higher than ∼0.2 GPa. Mechanisms of the negative linear compressibility of TBPA and EMN at the microscopic (molecular) level have been found for the first time. It was shown that NLC correlates with a baric change of spatial orientation (rotation) and linear dimensions of molecular structural units relative to crystallographic axes, as well as with a baric increase of intermolecular distances along the NLC direction. Quantum topological analysis of electron density was used to study intermolecular interactions. It has been established that TBPA and EMN crystals are optically transparent for visible light at pressures up to 1 GPa.
基于包含色散相互作用的密度泛函理论，在低于1吉帕的压力下研究了结晶态四溴邻苯二甲酸酐（TBPA）和硝酸1-乙基-3-甲基咪唑鎓（EMN）的压缩性。首次发现，EMN在高达约0.15吉帕的压力下表现出负线性压缩性（NLC），而TBPA在高于约0.2吉帕的压力下表现出显著的NLC。首次在微观（分子）水平上发现了TBPA和EMN负线性压缩性的机制。结果表明，NLC与分子结构单元相对于晶轴的空间取向（旋转）和线性尺寸的压力变化相关，也与沿NLC方向分子间距离的压力增加相关。利用电子密度的量子拓扑分析来研究分子间相互作用。已经确定，在高达1吉帕的压力下，TBPA和EMN晶体对可见光具有光学透明性。
