On experimental versus theoretically calculated properties of thiadiazole derivatives

Abstract

ABSTRACT:The recently published results of a theoretical calculation of the physicochemical properties of acenaphtho[1,2-c]-and phenanthro[9,10-c]-1,2,5-thiadiazole 1,1-dioxide, using a modified density functional theory (CHIH-DFT), are compared with our experimental results. The CHIH-DFT-calculated IR spectra of both compounds are also compared with those obtained using relatively simple RHF calculations. It is concluded that, in these cases, the improvements claimed for the new model chemistry are marginal. The IR spectra of three new derivatives of 1,2,5-thiadiazole are also reported and calculated.

Kinetics and mechanisms of flumequine degradation by sulfate radical based AOP in different water samples containing inorganic anions

“…The density functional theory (DFT) has been widely used as it can obtain the physicochemical properties of compounds to reveal their changing tendencies. 53 A large number of researchers have used DFT to calculate and predict the environmental behavior of organic pollutants, as well as conduct risk assessment on the toxicity of transformation products. 54 The quantum chemical parameters including the frontier orbital characteristics and charge distribution of FLU were calculated by Gaussian09 program according to DFT.…”

1,2,5-Thiadiazole 1,1-dioxides and Their Radical Anions: Structure, Properties, Reactivity, and Potential Use in the Construction of Functional Molecular Materials

“…Several theoretical works with a detailed description of selected dioxothiadiazole molecules have been published, providing some general insight into the computational methods best suited to yield satisfactory agreement with experimental data for this family of compounds [ 47 , 50 , 54 , 55 , 56 , 57 , 58 ]. The most popular methods for the calculation of dioxothiadiazole properties is standard and involve DFT with B3LYP hybrid functional and a 6-311G++(d,p) or 6-311G++(3df,3pd) basis set.…”

“…UV-Vis spectroscopy for the simplest 3,4-disubstituted 1,2,5-thiadiazole 1,1-dioxides has a maximum in the ultraviolet region (approximately 315 nm in MeCN and 240–280 nm in ethanol) with the molar absorption coefficient on the order of 10 3 dm 3 ·mol −1 ·cm −1 [ 68 , 72 , 73 ]. When the heterocyclic ring is fused to a larger aromatic system, the UV-Vis spectra become complicated, and the ε max often exceeds 10 4 dm 3 ·mol −1 ·cm −1 in the UV region [ 56 , 60 , 68 , 74 ].…”