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A TD‐DFT basis set and density functional assessment for the calculation of electronic excitation energies of fluorene
Author(s) -
Barboza Cristina Aparecida,
Vazquez Pedro Antonio Muniz,
MacLeod Carey Desmond,
ArratiaPerez Ramiro
Publication year - 2012
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.24300
Subject(s) - coupled cluster , fluorene , density functional theory , excitation , basis set , atomic physics , cluster (spacecraft) , range (aeronautics) , molecule , computational chemistry , chemistry , molecular physics , physics , materials science , quantum mechanics , computer science , nuclear magnetic resonance , polymer , composite material , programming language
Conjugated organic materials are the subject of intensive research for a range of optoelectronic applications. A model for such molecules is fluorene, which consists of rigid planar biphenyl units of C 2v symmetry. A low energy experimental absorption spectrum in the gas phase is composed of A 1 and B 2 transitions. The aim of this work is to evaluate the performance of the basis sets cc‐pVXZ (X = D and T), aug‐cc‐pVDZ, 6‐31G**, 6‐31++G**, 6‐311G**, 6‐311++G**, Sadlej‐pVTZ, Z2Pol, Z3Pol, and pSBKJC and of the functionals B3LYP, B3LYP/CS00, CAM‐B3LYP, PBE0, and LB94 in predicting the electronic transitions obtained taking linear response‐coupled cluster singles and doubles (LR‐CCSD) results as the theoretical reference. Our findings suggest that the time‐dependent density functional theory singles method is not able to correctly assign the predicted spectrum while LR‐CCSD always correctly describes the experimental data. Among the studied density functionals, the best performance was achieved by the CAMB3LYP. For transitions above 5 eV, diffuse functions are required to properly predict the observed transitions. © 2012 Wiley Periodicals, Inc.