Simon F. Bone, Bruce A. Smart, Hedi Gierens, Carole A. Morrison, Paul T. Brain and David W. H. Rankin
The molecular structure of thiazole has been determined by the joint analysis of data obtained from gas-phase electron diffraction (GED), microwave (MW) spectroscopy and abinitio molecular orbital calculations. The combined approach, making use of the SARACEN method, has led to a very precise structure in which all independent geometric parameters are well defined, and the quoted uncertainties reflect the true accuracy of the measurements. The ground-state average (≡rα° or rz) structural parameters obtained in the combined study of thiazole were; r[S(1)–C(2)]=172.37(11) pm, r[S(1)–C(5)]=171.38(13) pm, r[C(2)–N(3)]=131.0(2) pm, r[C(4)–C(5)] pm=136.90(19) pm, r[N(3)–C(4)]=137.2(2) pm, r[C(2)–H(6)]=109.8(4) pm, r[C(4)–H(7)]=109.9(4) pm, r[C(5)–H(8)]=109.7(4) pm, C(2)–S(1)–C(5)=89.41(4)°, S(1)–C(2)–N(3)=115.16(6)°, S(1)–C(5)–C(4)=109.52(8)°, C(2)–N(3)–C(4)=109.97(9)°, N(3)–C(4)–C(5)=115.95(11)°, S(1)–C(2)–H(6)=120.7(2)°, C(5)–C(4)–H(7)=125.0(4)°, S(1)–C(5)–H(8)=121.7(2)°.