A comparison of ground and excited state properties using SCC-DFTB and
semiempirical methods

John M. McKelvey, JMMcKel@attglobal.net, McKelvey Computational Chemistry, 10819
Middleford Pl, Ft Wayne, IN 46818 and Sergei Tretiak, Theoretical Division, Los
Alamos National Laboratory, MS B268, Los Alamos, NM 87545.

UV-VIS properties including absorbtion and emission band shapes and Lmax are
computed and compared using semiempirical and SCC-DFTB methods. Ground and
excited state geometries as well as absorbtion and emission band shapes are
compared for SCC-DFTB, AM1, NDDO_G, and in some cases B3LYP DFT methods, all
employing ground and excited state vibrational normal modes. In several cases
band shapes computed via refractive index and Duschinski procedures are
compared. Lmax results are compared for time-dependent DFTB, INDO/S, NDDO-G and
AM1 methods.