Silicon nitride, SiN, was identified in spectra recorded toward IRC+10216 by
B. E. Turner,
Detection of SiN in IRC +10216
Astrophys. J. 388, L35L38 (1992).
SiN is one of the few silicon containing molecules that have been observed
in the interstellar medium in this case in absorption toward Sgr B2(M):
P. Schilke, S. Leurini, K. M. Menten, and J. Alcolea,
Astron. Astrophys. 412, L15L18 (2003).
Even though only the J = 5/2 3/2 fine structure component of the N = 2 1 rotational transition was observed the resolved 14N hyperfine structure secures the detection.