Structural and energetic properties of benzoic acid\ncrystals at pressure elevated from ambient condition up to\n2.21 GPa were characterized. The directly observed variations\nof cell parameters and consequently cell volume are associated\nwith many other changes including energetic, geometric,\nand electronic characteristics. First of all the non-monotonous\nchange of lattice energy are noticed with the rise of pressure\nsince the increase of stabilization up to 1GPa is followed by\nsystematic decrease of lattice energies after extending the hydrostatic\ncompression. There is also an observed increase of\nC2 2 (8) synthon stabilization interaction with increase of pressure.\nThe lattice response rather than interaction within\nsynthons are source of observed pressure-related trend of lattice\nenergy changes. The energy decomposition analysis revealed\nthat the total steric interactions determine the overall\ntrend of lattice energy change with the rise of pressure. Besides\ngeometric aromaticity index was used as a measure of\ngeometric changes. Serious discrepancies were noticed between\nHOMA values computed with the use of experimental\nand optimized geometries of the ring. Even inclusion of uncertainties\nof experimental geometries related to limited precision\nof X-ray diffraction measurements does not cancel\nmentioned discrepancies. Although HOMA exhibit similar\ntrends at modest pressures the diversity became surprisingly\nhigh at more extreme conditions. This might suggest limitations\nof periodic DFT computations at elevated pressures and\nthe experimentally observed breaking of molecules at very\nhigh pressures will probably not be accounted properly in this\napproach. Also limitation of direct use of experimental geometries\nwere highlighted.
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