Prediction of charge transfer transition energies of the molecular complexes of PMDA with a series of methylbenzenes by TDDFT

Department of Chemistry, Netaji Mahavidyalaya, Arambagh, Hooghly-712 601, West Bengal, India

E-mail: amitstiwary@gmail.com

Manuscript received online 07 February 2019, revised 09 April 2019, accepted 07 May 2019

The functionals M06, M06-L, M06-2X and B3LYP were used to establish molecular complex formation and to calculate CT transition energies of the molecular complexes of PMDA with benzene, toluene, p-xylene, mesitylene and durene in CCl₄ medium by a TDDFT calculation under the PCM formalism. Using the ground state optimized geometries as starting points, attempts were made to calculate the CT transition energies of the molecular complexes by TDDFT/6-31++G(d,p). The calculated hν_CT values obtained by the different functionals were compared among themselves and also with experimentally reported values. Agreement of the calculated CT transition energies with experimental values is reasonably good, M06 results being closest. The lowest energy CT absorption bands as calculated by TDDFT were found to abide by the theory of charge transfer complexes given by Mulliken (J. Am. Chem. Soc., 1952, 74, 811).