Ab Initio Study of the Dynamical Si–O Bond Breaking Event in α-Quartz
SU Rui1, ZHANG Hong1, HAN Wei2, CHEN Jun3,4**
1College of Physical Science and Technology, Sichuan University, Chengdu 610064 2Research Center of Laser Fusion, Mianyang 621900 3Institute of Applied Physics and Computational Mathematics, Beijing 100094 4Center for Applied Physics and Technology, Peking University, Beijing 100871
Abstract：The Si–O bond breaking event in the -quartz at the first triplet (T1) excitation state is studied by using ab initio molecular dynamics (AIMD) and nudged elastic band calculations. A meta-stable non-bridging oxygen hole center and center (NBOHC-E') is observed in the AIMD which consists of a broken Si–O bond with a Si–O distance of 2.54?. By disallowing the re-bonding of the Si and O atoms, another defect configuration (III-Si/V-Si) is obtained and validated to be stable at both ground and excitation states. The NBOHC-E' is found to present on the minimal energy pathway of the initial to III-Si/V-Si transition, showing that the generating of the NBOHC-E' is an important step of the excitation induced structure defect. The energy barriers to produce the NBOHC-E' and III-Si/V-Si defects are calculated to be 1.19 and 1.28 eV, respectively. The electronic structures of the two defects are calculated by the self-consistent GW calculations and the results show a clear electron transition from the bonding orbital to the non-bonding orbital.
(Density functional theory, local density approximation, gradient and other corrections)
引用本文:
. [J]. 中国物理快报, 2015, 32(10): 107803-107803.
SU Rui, ZHANG Hong, HAN Wei, CHEN Jun. Ab Initio Study of the Dynamical Si–O Bond Breaking Event in α-Quartz. Chin. Phys. Lett., 2015, 32(10): 107803-107803.
2015, Vol. 32 
