TY - GEN AU - Lorenz,Marco AU - Usvyat,Denis AU - Schütz,Martin TI - Local ab initio methods for calculating optical band gaps in periodic systems. I. Periodic density fitted local configuration interaction singles method for polymers SN - 1089-7690 PY - 2011///0613 KW - Polymers KW - chemistry KW - Quantum Theory N1 - Publication Type: Journal Article; Research Support, Non-U.S. Gov't UR - https://doi.org/10.1063/1.3554209 ER -