Fluorescence quenching, DFT, NBO, and TD-DFT calculations on 1, 4-bis [2-benzothiazolyl vinyl] benzene (BVB) and meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) in the presence of silver nanoparticles

Abstract

Steady-state fluorescence measurements were used to examine the fluorescence quenching of 1, 4-bis [-(2-benzothiazolyl) vinyl benzene (BVB) by sodium salt of meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) in the presence and absence of silver nanoparticles (Ag NPs). The energy transfer (ET) process’s emission intensities and Stern–Volmer constants (KSV) showed that Ag NP’s presence increased ET’s efficiency. The molecular structures of TPPS, TPPS, and BVB/TPPS were optimized using the DFT/B3LYP/6-311G (d) technique to elucidate the mechanism. The discovered optimized molecular structure proved that whereas TPPS and BVB/TPPS MSs are not planar because the porphyrin group in TPPS is rotated out by phenyl sodium sulphate, the BVB MS is planer. All of the theoretical BVB results and the acquired experimental optical results were very similar.