A structural and vibrational study of dehydrofukinone combining FTIR, FTRaman, UV–visible and NMR spectroscopies with DFT calculations

Structural and spectroscopic studies of two 1,3-benzothiazole tautomers with potential antimicrobial activity in different media. Prediction of their reactivities

“…Note that the calculated shifts for the H15 nuclei belonging to the N-H bond in thione and to the S-H bond in thiol have lower values than the experimental ones; therefore, they show higher differences probably due to the dimeric species of thione that could also be in solution. On the other hand, the calculated shifts for the 13 C nucleus demonstrate a reasonable concordance by using the 6-311++G** basis set when the values are compared with available experimental values for the benzene ring [42][43][44][45][46].…”

“…The strong IR bands at 3095 and 3062 cm -1 are easily assigned to the C-H stretching modes of the four forms studied here by comparison with similar compounds containing these groups [37][38][39][40][42][43][44][45][46]. The expected in-phase and out-ofphase modes are predicted in the expected regions; hence, these modes are assigned accordingly, as observed in Table 4.…”

“…The B3LYP/6-311++G** level of theory was employed only to calculate the chemical shifts of the 1 H NMR and 13 C NMR spectra by using the GaugeIndependent Atomic Orbital (GIAO) method [42] because this basis set produce the best results, as reported for other species [43][44][45][46][47]. Hence, the NMR calculations were performed using TMS as reference and that basis set.…”

Experimental study on the structure and vibrational, thermal and dielectric properties of bis(2-methylanilinium) selenate accomplished with DFT calculation

“…For assignment of phenyl ring modes the classical work of Herzberg [21] as well as the paper by Miller [22] is phenyl ring. [23]. The weak band observed at 1472 cm -1 and the medium band observed at 1495 cm -1 sy ( CH 3 ).…”

“…The two very weak bands observed at 3051 and 3121 cm -1 are assigned to the symmetric ( s (CH 3 )) and asymmetric ( a s (CH 3 )) stretching mode, respectively [23]. The asymmetric stretching mode correspond to (C-H) ar is observed by one broad band located at 3306 cm -1 .…”