National Radio Astronomy Observatory
National Radio Astronomy Observatory
SiCN is a linear radical with a X 2
electronic ground state.
Its rotational spectral lines appear as a series of lambda-doubled transitions
with further splitting owing to lambda doubling and magnetic hyperfine
structure. All three doublets lying within the upper portion of the
atmospheric 3mm window were detected, though some were contaminated by
other lines, in observations at the IRAM 30m telescope towards
IRC+10216.
D=2.9 D
Spectroscopic constants from Apponi, A. J., McCarthy, M. C., Gottlieb, C. A. & Thaddeus, P. 2000, ApJL, 536, L55:
Spectroscopic Constants of SiCCH, SiCN, and SiNC in the X 2 State (in MHz) |
| Parameter | SiCCH | SiCN | SiNC |
A +  a... | 2169000(4000) | 2124000(6000) | 1763000(4000) |
| B... | 5436.6629(2) | 5543.4152(2) | 6396.6839(3) |
| D... | 0.0018244(5) | 0.0023102(2) | 0.0028890(4) |
| a... | 1161(9) | 2070(10) | 2470(10) |
| p + 2q... | 32.071(2) | 25.734(2) | 9.800(3) |
| (p + 2q)D... | -0.000420(7) | -0.000386(7) | 0.01842(3) |
| q... | 0.807(4) | 0.869(2) | 1.385(7) |
| qD... | -0.000016(2) | ... | 0.000011(7) |
| a - (b + c)/2... | 14.969(5) | 15.676(2) | 3.206(4) |
| b... | -14.1(3) | 5.6(2) | -5.2(3) |
| d... | 9.475(3) | 20.033(2) | 2.706(4) |
| eQq0... | ... | -5.031(3) | -1.417(2) |
| eQq2... | ... | 2.3(5) | ... |
| rms... | 0.019 | 0.032 | 0.034 |
Interstellar detection by Gu\'elin, Muller, Cernicharo, Apponi, McCarthy, Gottlieb and Thaddeus A&A 363, L9 2000.
Laboratory work by Apponi, A. J., McCarthy, M. C., Gottlieb, C. A. & Thaddeus, P. 2000, ApJL, 536, L55