The solid molecular hydrogen under hydrostatic pressure varying from 0 up to 2.2$2.2$ GPa at low temperatures is studied by path-integral Monte Carlo simulations in the isothermal-isobaric ensemble. The quantum contribution to the vibrational energy lies between 40%$40\%$ and 90%$90\%$ of their total values. The zero-point energy increases with increasing pressure and the anharmonicity is more pronounced at low temperature and pressure. A satisfactory agreement between our simulation results and available experimental measurements has been achieved. At very low temperatures, the quantum effects are responsible for softening the molecular crystal in about 1 GPa in the studied range of pressure.

静水压力下的固体分子氢在0至2.2之间变化$2.2$通过等温-等压集成中的路径积分蒙特卡罗模拟研究了低温下的GPa。量子对振动能量的贡献介于40％$40％$和90％$90％$他们的总价值。零点能量随压力增加而增加，并且在低温和低压下非谐性更加明显。我们的模拟结果与可用的实验测量结果之间已达成令人满意的协议。在非常低的温度下，在所研究的压力范围内，量子效应导致分子晶体在约1 GPa的压力下软化。