LIF excitation spectra for S0→S1 transition of deuterated anthranilic acid COOD, ND2 in supersonic-jet expansion

Theoretical Modeling of Deuteration-Induced Shifts of the 0–0 Bands in Absorption Spectra of Selected Aromatic Amines: The Role of the Double-Well Potential

“…Apart from the theoretical work, we also measured the LIF excitation spectra for all three cyanoanilines seeded in the supersonic jet, with three levels of deuteration (0%, ∼50%, and ∼90%). The experimental setup and methodology of recording of the spectra were described in our previous work . Figure shows the energy region of the 0–0 transition, in which the origin bands of the excitation spectra are visible.…”

“…In view of the above results, one may safely conclude that the energy barrier for inversion in AA is very low, probably between 40 and 55 cm −1 , which is in accordance with the observations that AA is dynamically planar in the ground state. 12,34 Moreover, it seems that using the energy barrier obtained at the CC2/aug-cc-pVXZ (X = D,T) or CC2/cc-pVQZ levels of theory, instead of the explicitly correlated results or the CBSextrapolated values, would not introduce significant errors into the model calculations (for details of the energy barrier influence on the results of the model calculations, the reader is referred to the Supporting Information). On the other hand, it would have the advantage of consistencythe geometries, vibrational analyses for both the ground and the excited state, and the energy barrier would be obtained with the same method and basis set.…”

“…Moreover, in the supersonic jet experiments, even an initially pure, fully deuterated species (DDD-AA) undergoes a reverse substitution reacting with traces of water present in the experimental setup. 12 In such a situation, analysis of the highly resolved vibronic spectra from the SS-Jet measurements becomes a formidable task, as they consist of the complex overlapping structures corresponding to various isotopomers. An independent way to estimate the relative positions of the electronic origins of the spectra for different isotopomers would certainly aid the analysis of the experimental results.…”

“…Unfortunately, this process usually leads to a mixture of isotopomers, their relative concentrations depending on the D 2 O/H 2 O ratio. Moreover, in the supersonic jet experiments, even an initially pure, fully deuterated species (DDD-AA) undergoes a reverse substitution reacting with traces of water present in the experimental setup . In such a situation, analysis of the highly resolved vibronic spectra from the SS-Jet measurements becomes a formidable task, as they consist of the complex overlapping structures corresponding to various isotopomers.…”

Quantitatively Adequate Calculations of the H-Chelate Ring Distortion upon the S0 → S1(ππ*) Excitation in Internally H-Bonded o-Anthranilic Acid: CC2 Coupled-Cluster versus TDDFT

“…LIF excitation spectra of AA of improved resolution, better S/N ratio and minimized saturation effects − provided extensive experimental data for the Franck–Condon analysis of the S 0 → S 1 transition based on the TD-DFT and CIS (single CI) calculations . The FC analysis and the studies of other aniline derivatives showed that the band intensities computed using the CIS method, and hence the geometry changes, are drastically underestimated, especially ortho -substituted molecules.…”