A Computational and Structural Database Study of the Metal-Carbene Bond in Groups IA, IIA, and IIIA Imidazol-2-Ylidene Complexes

Table 1

The number of entries (hits), coordination number (CN), and bond parameters of group IA metal-imidazol-2-ylidene complexes.

Metal	CN	No. of hits	D (M-Im) (Å)			Im-M-X angle (°)
			Mean	Range	St dev.	Mean	St dev.
Li	2	3	2.141	2.075–2.178	0.034	170.23	12.45
	3	15	2.131	2.018–2.335	0.073	123.6	13.75
	4	20	2.191	2.047–2.338	0.062	111.8	18.09
	5	2	2.111	2.103–2.119	0.008	106.2	19.31
	6	1 (MALRAS)	2.156
Na	2	4	2.447	2.439–2.46	0.007	169.5	3.45
	3	3	2.46	2.388–2.577	0.062	124.3	39.63
	4	7	2.505	2.468–2.551	0.027	119.2	7.87
K	2	6	2.915	2.81–3.199	0.158	178	5.41
	3	2	3.008	2.989–3.024	0.030	133.3	3.79
	4	4	2.928	2.901–2.954	0.030	100.6	19.31
	5	3	3.054	2.921–3.132	0.099	108.4	32.67
	6	1 (QUGDUT)	2.888
	7	1 (OCOXUA)	2.896
	8	1 (DIQLUM)	3.067