Structural, electronic, and optical properties of crystalline iodoform under high pressure: A first-principles study

摘要

The high pressure phases, electronic structure, and optical properties of iodoform at zero temperature have been investigated by first-principles pseudopotential plane-wave calculations based on the density-functional theory. A new high pressure polar monoclinic structure with space group Cc, denoted as phase, has been observed after a series of simulated annealing and geometry optimizations. Our calculated enthalpies showed that the transition from to phase occurs at 40.1 GPa. Electronic structure calculated results showed that the insulator-metal transition in phase due to band overlap is found at about 32 GPa. In addition, the calculated absorption spectra of iodoform are consistent with the experimental results.