Polarization IR spectra of the hydrogen bond in 2-oxazolidone crystals: isotopic dilution effects in the crystalline spectra

H/D isotopic “self-organization” effects in the infrared spectra of cyclic tetramers of hydrogen bonds: Polarized spectra of 7-azaindole crystals

“…All the facts listed above are highly non-conventional in the IR spectroscopy of the hydrogen bond in molecular crystals, illustrating an abnormal spectral behavior of 7-azaindole crystals. These distinguish the spectral properties of the system with respect to the analogous properties of the majority of hydrogen-bonded molecular crystals [6][7][8]10,[11][12][13]16]. We will show that a successful explanation of these spectral effects needs taking into the account in the proposed theoretical model, not only of the most recent quantitative theories, but also of a number of newly described mechanism.…”

“…Such effects were also identified in spectra of some crystalline systems with cyclic trimers, as well as of crystals with open chains of hydrogen bonds in their internal structures [6,8]. In the spectra of another sub-group of crystals, which also present infinite hydrogen bond chains, the H/D isotopic ''selforganization'' effects did however not appear [14][15][16].…”

“…This fact cannot be directly related to the substantial change in the spatial structure of 7-azaindole associates. It resulted from our recent studies that the spectra of cyclic hydrogen bond dimeric systems [7,10,[11][12][13] basically differed from the spectra of chain hydrogen bond systems in crystals [5,6,8,16]. We should, therefore, expect that the IR spectra of 7-azaindole would be highly sensitive on changes in the hydrogen bond system geometry.…”

Effects of “excessive” exciton interactions in polarized IR spectra of the hydrogen bond in 2-butynoic acid crystals: Proton transfer induced by dynamical co-operative interactions involving hydrogen bonds

“…The circumstances, in which the ''self-organization" effects did not appear, were also established [19][20][21]. It turned out that the electronic structure of the associating molecules, affecting the magnitude of the dynamical co-operative interaction energies, was the dominant factor responsible for such behavior [16][17][18][19][20][21].…”

Vibronic model for H/D isotopic “self-organization” effects in hydrogen bond cyclic trimeric systems: 4-Bromopyrazole crystal IR spectra

“…Most probably, when a cycle dimension grows, some essential restrictions in the H/ D isotopic ''self-organization'' mechanisms should appear, as only some of the chain systems exhibited these effects in their IR spectra [22,24]. In the spectra of another group of the chain systems these effects were absent [20,21,29]. Therefore our aim was also to check experimentally, if the H/D isotopic ''self-organization'' effects appeared in the IR spectra of the trimer hydrogen-bonded model, in the way predicted by the proposed theoretical model.…”