Theoretical and experimental investigation on the electrochemical properties, structural and spectroscopic parameters of 6,7-dihydroxy-9-thia-1,4a-diaza fluoren-2-one (DTDFO)

Abstract

Using density functional theory, ¹³CNMR chemical shifts, IR spectra, electrode potential and structural parameters of 6,7-dihydroxy-9-thia-1,4a-diaza fluoren-2-one (DTDFO) as an important derivative of the thiadiazaflourenone compounds are calculated. The calculated electrochemical properties are compared with those obtained by cyclic voltammetry showing 9% and 6% error for the MPW1PW91 and B3LYP levels of theory, respectively. Furthermore, actual IR and ¹³CNMR spectra are obtained and compared with the theoretical results at both the levels; linear correlations between the experimental IR and ¹³CNMR data and their corresponding theoretical ones are found with R² > 0.90. Other helpful descriptors such as Fukui functions, delocalization stability energies, and molecular electrostatic potentials are used to characterize the reactivity and electronic properties of the title structure. The two employed computational methods, namely B3LYP/6-311++G(d,p) and MPW1PW91/6-311++G(d,p) are also compared with each other. Statistical methods such as root mean squared errors (RMSE), and mean absolute errors (MAE) are adopted to measure the errors arising from the computations. In conclusion, an acceptable agreement between the theoretical and experimental data shows the reliability of the employed computational methods in this study. Moreover, this work provides a detailed theoretical insight into the different aspects of DTDFO, some of which are supported by experimental evidence.

GRAPHICAL ABSTRACT

KEYWORDS:

• Density functional theory
• cyclic voltammetry
• electrode potential
• Gibbs free energy
• electronic properties
• NMR

Acknowledgements

The authors gratefully acknowledge the support of Prof. Saeed Shahrokhian and Dr. Ali Hamzehloei in providing them with the cyclic voltammogram of DTDFO (Figure 7); the authors confirm that the appropriate third-party permissions (license number: 4587030252266) have been taken to reuse the above-mentioned figure from ref. [14]. The authors would like to thank the Semnan University Research Council for the financial supports of this work.

Disclosure statement

No potential conflict of interest was reported by the authors.