Degradation by hydrolysis of three triphenylmethane dyes: DFT and TD-DFT study

Djamel Taharchaouche , Nadjia Latelli (1, 2) , Hafida Merouani (3) , Boussebbat Wahiba , Naima Mechehoud , Nadia Ouddai (4) , Christophe Morell (5, 6, 7) , Lynda Merzoud (8) , Henry Chermette (8)

1 département de chimie
2 Laboratoire chimie des matériaux et des vivants: activité, réactivité
3 Lab Chim Mat & Vivants Act
4 Université de Batna - Université de Batna
5 ISA - Institut des Sciences Analytiques
6 ISA-Theoretical chemistry and A.I. - Chimie théorique et Intelligence artificielle
7 UCBL - Université Claude Bernard Lyon 1
8 Chemometrics and theoretical chemistry. - Chimiométrie et chimie théorique

DFT reactivity descriptors, the ultraviolet-visible spectra and hydrolysis mechanism of three cationic dyes (Malachite Green (MG), Brilliant Green (BG) and Ethyl Green (EG)) are performed with several exchange-correlation functional (global GGA, hybrids and rangeseparated). Using time-dependent density functional theory the theoretical ultravioletvisible absorption spectra of the three cationic dyes are obtained and obey the trend for the λ max : GGA > hybrid > range-separated functional. Thanks to the transition state theory, the barriers of hydrolysis mechanism of the cation structures dyes were obtained in gas and solution phase. It is shown that, for these systems the barriers are in order: BG + < MG + < EG 2+ in gas and solution phase. In the two phases, the CAM-B3LYP functional gives the highest barriers and the M06 gives the lowest ones.

Mots clés: dye Triphenylmethane DFT TD-DFT degradation; dye; Triphenylmethane; DFT; TD-DFT; degradation

Domaines: Chimie

Djamel Taharchaouche, Nadjia Latelli, Hafida Merouani, Boussebbat Wahiba, Naima Mechehoud, et al.. Degradation by hydrolysis of three triphenylmethane dyes: DFT and TD-DFT study. Theoretical Chemistry Accounts: Theory, Computation, and Modeling, 2023, 142 (1), pp.10. ⟨10.1007/s00214-022-02950-1⟩. ⟨hal-03917879⟩