Quantitative beschreibung der UV-S-absorptionen einfacher thiocarbonylverbindungen

Preparation, crystal and molecular structures of Ph2CNSNSO and a comparison of the —SNSO and —SNSS chromophores

“…"The appearance of two bands is the result of an excitonic coupling of the two chrornophores. similar trend has been observed for the .rr + .rr* transition energies of carbonyls (30) and thiocarbonyls (31).…”

A comparison of some properties of C=O and C=S bonds

“…14 The n→π* transitions for many thiocarbonyl compounds have been located in cyclohexane solution. 15 They are easily observed because they are well separated from other transitions. The corresponding carbonyl n→π* transitions are more difficult to locate because they give broad bands that are near other transitions.…”

“…2 Another interesting difference is found in the position of the n-π* transition that is shifted into the visible spectrum by the sulfur. 3 As a result the thiocarbonyl derivatives have interesting colors with phenyl thiocarbonyl chloride being red (λ max = 530 nm). The transitions are shifted by about 2eV (~50 kcal/mol) to the red as compared to the corresponding carbonyl compounds.…”

Ab Initio Investigation of then→ π* Transitions in Thiocarbonyl Dyes

“…Experimentally, the first systematic studies of the UV-vis spectra of these molecules began in the sixties with the works of Janssen, 6,7 Sandström, [8][9][10][11][12] and Korver et al 13, 14 Fabian, Mayer, and coworkers soon rationalized these absorption spectra by using a combination of measurements and semiempirical theoretical results. [15][16][17] More recently, experimental high-resolution analysis of the spectra of small gas-phase thiocarbonyl derivatives have been performed by Moule, Clouthier, and co-workers. [18][19][20][21] This work aims at further investigating the wavelength of maximum absorption (λ max ) of a series of thiocarbonyl dyes by using ab initio quantum chemical approaches.…”

“…For instance, additive procedures (i.e., group contributions) have successfully been designed for anthraquinones 23 and thiocarbonyls. 15 Though these rules are of practical interest, they are often nontransferable to other families of dyes and, more importantly, are limited by the experimental input. Indeed, they are unable to foresee the spectra of a given chromophore substituted by new auxochroms.…”