Dynamic and electrooptical properties of FH…F and FH…N hydrogen bridges

The dynamic and electrooptical parameters of the hydrogen bridges in (HF)₂, FH…FCD₃, FH…NCH, and FH…NCCH₃ complexes were calculated by the MINDO/3 method. Relationships between these parameters have been found. These parameters for the F−H…Y bridges mainly coincide with the relationships previously established for the hydrogen O−H…Y bridges. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1067–1069, May, 1997.     

Syntheses of some substituted sym-triazines

The synthesis of various -substituted propionimidic esters has been effected and the conditions of their conversion into the corresponding 2,4,6-triethyl-sym-triazine derivatives have been studied.     

Characteristic features of the reaction of 3(5)amino-5(3)-methylpyrazole with 1-nitroanthraquinone-2-carboxylic acid

In the reaction of 3(5)-amino-5(3)-methylpyrazole with 1-nitroanthraquinone-2-carboxylic acid in sulfolane at 150°C, 2-methyl-pyrazolo[5,1-b]naphtho[2,3-h]quinazoline-5,10,13-trione is formed with an admixture of 1-aminoanthraquinone-2-carboxylic acid and 1-aminoanthraquinone. Under similar conditions, from 4-amino-1,5-dimethylpyrazole, only 1-(1,5-dimethyl-4-pyrazolylamino)anthraquinone-1-carboxylic acid is formed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1191–1192, September, 1992.     

Molecular and crystal structure of 2-para-toluimido-4,4-dimethyl-(4H)-1,3-thiazine

The imino structure of 2-p-toluimido-4,4-dimethyl-(4H)-1,3-thiazine (I) was demonstrated by x-ray diffraction structural analysis. Molecules of I in the crystal are linked by N-HO hydrogen bonds in infinite chains. A shortened SO intramolecular contact was found which corresponds to a secondary interaction. A mechanism was proposed for the thiazoline-thiazine rearrangement.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1638–1643, December, 1984.     

A characterization of the Raman modes in a J-aggregate-forming dye: a comparison between theory and experiment

J-Aggregates are a class of organic molecules that possess several interesting characteristics that make them attractive for a range of organic-based optoelectronic devices. We present experimental and computer-simulation studies of the Raman-active vibrational modes in the J-aggregate-forming dye 5,6-dichloro-2-[[5,6-dichloro-1-ethyl-3-(4-sulfobutyl)benzimidazol-2-ylidene]propenyl]-1-ethyl-3-(4-sulfobutyl)benzimidazolium hydroxide, sodium salt, inner salt. The molecular monomer and dimer are analyzed computationally and the Raman mode energies extracted. There is a good agreement between the energies of the theoretical and experimental Raman modes. Experimentally, an enhancement is seen in the intensity of two low frequency modes upon aggregation of the dye. This is attributed to aggregation-enhanced Raman scattering. An enhancement is also observed in certain modes of the calculated spectra upon changing from a monomer to dimeric arrangement. A link is suggested between the Raman-active vibrational modes of the molecule, and a time-dependent electronic coupling present over several molecules.     

Integration by Parts for Poisson Processes

Using a perturbation of the rate of a Poisson process and an inverse time change, an integration by parts formula is obtained. This enables a new form of the integrand in a martingale representation result to be obtained.