摘要:

The application of matrix isolation techniques connected with quantum mechanical calculations on generation and structural elucidation of cumulenic compounds containing sulfur or oxygen has been reviewed. Experimental matrix IR and UV/VIS data for all known species of this class of substances have been summarized together with some matrix electron spin resonance (ESR) studies.

ISSN:0196-1772    

DOI:10.1080/01961779908047947

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

This review describes the applications of tandem mass spectrometry methodologies for the preparation and identification of ionized and neutral heterocumulenes S=C=(C)n=C=X in the gas phase.

ISSN:0196-1772    

DOI:10.1080/01961779908047948

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The 21 experimentally known systems of the types CnX and XCnY (X, Y = O, S;n= 2–6) have been calculated at common levels of theory. The geometries, vibrational wave-numbers and absorption intensities, rotational constants, dipole moments, bond dissociation energies, singlet‐triplet energy gaps for the 11 diradicals, as well as UV absorptions are presented and discussed, and compared with the experimental values where this is possible. The calculated resonance structures, the C‒C bond alternation, the extremely low bending wavenumbers, and the dramatic increase of the dipole moment and IR absorption intensity upon chain lengthening for CnX strongly suggest the term heteropolyacetylene rather than the name shown in the title. Nevertheless, all these zwitterionic systems exhibit significant π-electron delocalization to an extent which is known from aromatic compounds.

ISSN:0196-1772    

DOI:10.1080/01961779908047949

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

This review introduces the present status of interstellar chemistry and shows why various carbon-chain molecules occupy a key position among hundred or more interstellar molecules so far identified. Then, several series of sulfur-bearing carbon-chain molecules such as CnS, HCnS, CnS2, CnOS, and CnO2are reviewed especially by paying attention to their generation and spectroscopic characterization in the laboratory.

ISSN:0196-1772    

DOI:10.1080/01961779908047950

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

This review summarizes the syntheses and reactions of carbon subsulfide, S=C=C=C=S. Carbon subsulfide can be synthesized for preparative purposes by decomposition of carbon disulfide in an electric arc. For spectroscopic purposes the thermolysis of S-heterocyclic precursors is described as a way which has found much interest. Reactions of carbon subsulfide are mainly cyclizations with 1,3-binucleophilic agents to give six-membered heterocycles, oxidative addition of platinum metal complexes or self-condensation to polymeric (C3S2)x.

ISSN:0196-1772    

DOI:10.1080/01961779908047951

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0196-1772    

DOI:10.1080/01961779908047946

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor