2018 年 17 巻 3 号 p. 127-129
The divide-and-conquer (DC) method was extended to time-dependent density functional tight-binding (TDDFTB) theory to enable excited-state calculations of large systems, as denoted by DC-TDDFTB. In this article, the implementation of TDDFTB and DC-TDDFTB methods into our in-house program, DC-DFTB-K, is explained. Dependence of CPU time on system-size for the DC-TDDFTB calculations indicates significant reduction of computational cost by adopting the DC method. Owing to the feature, excited-state calculations for whole photoactive yellow protein (PYP) surrounded by 4684 water molecules could be carried out in order to examine the hydrogen bond between p-coumaric acid and Glu46 in PYP.