Comparison of Real-Time and Linear-Response Time-Dependent Density Functional Theories for Molecular Chromophores Ranging from Sparse to High Densities of States

Samat Tussupbayev; Niranjan Govind; Kenneth Lopata; Christopher J Cramer

doi:10.1021/ct500763y

Comparison of Real-Time and Linear-Response Time-Dependent Density Functional Theories for Molecular Chromophores Ranging from Sparse to High Densities of States

J Chem Theory Comput. 2015 Mar 10;11(3):1102-9. doi: 10.1021/ct500763y. Epub 2015 Feb 5.

Authors

Samat Tussupbayev¹, Niranjan Govind², Kenneth Lopata³, Christopher J Cramer¹

Affiliations

¹ Department of Chemistry, Supercomputing Institute, and Chemical Theory Center, University of Minnesota , Minneapolis, Minnesota 55455, United States.
² Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory , Richland, Washington 99338, United States.
³ Department of Chemistry and Center for Computation & Technology, Louisiana State University , Baton Rouge, Louisiana 70803, United States.

PMID: 26579760
DOI: 10.1021/ct500763y

Abstract

We assess the performance of real-time time-dependent density functional theory (RT-TDDFT) for the calculation of absorption spectra of 12 organic dye molecules relevant to photovoltaics and dye-sensitized solar cells with 8 exchange-correlation functionals (3 traditional, 3 global hybrids, and 2 range-separated hybrids). We compare the calculations with traditional linear-response (LR) TDDFT and experimental spectra. In addition, we demonstrate the efficacy of the RT-TDDFT approach to calculate wide absorption spectra of two large chromophores relevant to photovoltaics and molecular switches. RT-TDDFT generally requires longer simulation times, compared to LR-TDDFT, for absorption spectra of small systems. However, it becomes more effective for the calculation of wide absorption spectra of large molecular complexes and systems with very high densities of states.