A Density Functional Theory Approach to the EPR Parameters of 2,6-Di-Tert-Butyl-4-Methylphenol Radical: Hyperfine Coupling Constant and g-Tensor Analysis

Abstract

Density functional theory (DFT) calculations were used to study the hyperfine coupling constant and g-tensor electron paramagnetic resonance parameters of the 2,6-di-tert-butyl-4-methylphenol radical. To investigate basis sets and DFT methods effects on hyperfine coupling constants and g-tensors of 2,6-di-tert-butyl-4-methylphenol radical were used UB3LYP and UCAM-B3LYP methods with the 6-31G(d), 6-31+G(d), 6-31G(d,p), 6-311G(d), 6-31++G(d), 6-31+G(d,p), 6-311+G(d), 6-311G(d,p), 6-31++G(d,p), 6-311++G(d), 6-311+G(d,p), 6-311++G(d,p), EPR-II and EPR-III basis sets. Theoretically calculated values for the 2,6-di-tert-butyl-4-methylphenol radical are in reasonable agreement with the experimental data. Additionally, the shifts g from the free electron g_e were analyzed in detail as the sum of three contributions. The spin-orbit interactions were found to be the dominant factor concerning the g. This study thus demonstrated the significant potential of DFT calculations for advanced EPR analysis.

Keywords

• EPR
• B3LYP
• CAM-B3LYP
• Hyperfine coupling constant
• g-tensor

Ethical Statement

Ethics committee approval was not required for this study because of there was no study on animals or humans.

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