Silicon carbide in circumstellar environment

  title={Silicon carbide in circumstellar environment},
  author={G. Pascoli and Michel Comeau},
  journal={Astrophysics and Space Science},
The presence of small clusters of silicon carbide (SiC) in circumstellar dust shells surrounding late-type stars is inferred from a broad emission feature peaking at around 11µm in infrared spectra [1]. These clusters are expected to condense from molecular arrangements composed of a few carbon and silicium atoms which are present in stellar winds surrounding carbon-rich late-type stars. We have searched for the possible geometric structures of SiCn+ radicals (n ≤ 5) on the basis ofab initio… 

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Structures and properties the lead-doped carbon clusters PbCn/PbCn+/PbCn- (n=1-10)

A systemic density functional theory study of the lead-doped carbon clusters PbCn/PbCn+/PbCn− (n=1–10) has been carried out using B3LYP method with both CEP-31G and TZP+ basis sets. For each species,

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A recent count of the stars leaving the main sequence and the method to estimate the return of matter to the interstellar medium due to mass-loss is summarized. Stars of (1 - 5) M⊚ would replenish

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SiC2 has been prepared in a supersonic molecular beam by laser vaporization of a silicon carbide rod within a pulsed supersonic nozzle. Rotational analysis of the 0‐0 band of the well‐known 4980 A

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Geometrical structures and vibrational frequencies of the energetically low‐lying isomers of SiC3

The ground state of the SiC3 molecule is found to be a closed‐shell cyclic C2v symmetry structure which can be described as a four‐membered ring with a transannular (cross ring) carbon–carbon bond,

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Accurate ab initio calculations are performed to study the structures and energies of small carbon clusters (Cn, n=2–10). The effects of polarization functions and electron correlation are included

The abundance distribution of C4H in IRC + 10216

We have observed the N=9-8 spin doublet emission line of C 4 H at 85.6 GHz in the carbon star IRC +10216 with the BIMA millimeter interferometer. The aperture synthesis images have an angular