We analyzed the excited-state structures and emission spectra of firefly emitter, the anionic keto form of firefly oxyluciferin（keto-l）, determined by the time dependent-density functional theory（TD-DFT） approach. The analysis is based on a direct comparison with the highly correlated CASSCF（MS-CASPT2） ab initio approach. 49 DFT functionals were considered and applied to the study. Among the tested functionals, mPW3PBE, B3PW91 and B3P86 give the best performance for ground-state geometry, absorption spectrum, excited-state geometry and emis- sion spectrum.
MIN Chun-gangLENG YanYANG Xi-kunREN Ai-minCUI Xiao-yingXU Ming-liWANG Shao-hua
