Experimental and theoretical studies of electronic energy states of methyl benzoate derivatives

Experimental and theoretical spectroscopic studies of ortho derivatives of methyl p-dimethylaminobenzoate

“…The absorption spectrum of the reference compounds a, b and c (given in the panel 0 for comparison) possesses two (a) or three (b and c) bands in the spectral region 200-350 nm. The peculiarities of those bands have been discussed in our former paper [18]. Here we would like to point that -OCH 3 or -OH group ortho substituted to the benzene ring of MB causes a red shift of all absorption bands and its change of intensity.…”

“…The efficiency of the CT reaction of a given molecule depending on the polarity of the solvent is determined by the R I Fl ðLEÞ dn= R I Fl ðICTÞ dn ratio and r value. [18], which demonstrates that the emitting molecules create a spectroscopic inhomogeneous assemble. The fluorescence/phosphorescence intensity ratio of III shows a reverse dependence, i.e., its value equals about 0.2 for EtOH and $0.06 McH glasses, respectively.…”

“…S 1 ð 1 L b Þ band of benzene and MB [18] (see Table 2). It must be noted, that the participation coefficients, n w m , for the corresponding transition differ from each other for each molecule.…”

“…Our previous papers [6,7,17,18] devoted to spectroscopic studies of single (ortho or para) substituted derivatives of methyl benzoate (MB) have been focused on the luminescence properties and its dependencies on the kind of solvent, excitation wavelength and temperature of the environment. In the presented communication we focus on the steady-state spectroscopic measurements of ortho-substituted derivatives of methyl p-dimethylaminobenzoate-I (Mp-DMAB), methyl o-methoxy p-dimethylaminobenzoate-II (Mo-Mxp-DMAB) and methyl o-hydroxy p-dimethylaminobenzoate-III (Mo-Hxp-DMAB).…”

Luminescence studies of o-hydroxy p-amino and p-dimethylamino methyl benzoate

“…Taking into consideration the results of our earlier spectroscopic studies [15,[17][18][19]37] and other authors [1][2][3][4][5][6][7][8][9][10][11][12][13]16,[20][21][22][23][24][25][26][27][28][29]38], we suppose that the molecules under study can appear as: keto rotamers a and b, zwitterionic and enolic tautomeric forms. Some of them already appear in the S 0 state, others are formed in a photoinduced proton-transfer reaction and appear in S 1 state only.…”