Table 2.

Selected Bond Length (Å) and Angles (deg) for complexes [2][BF₄], [3][BF₄]₃, and [5][BF₄]^a,b.

	[2][BF4]	[3][BF4]	[5][BF4]	[Fc][BF4]
Ccarbene−N	1.344[6]	1.349[6]	1.351[3]	-
Ccarbene−Au	2.015[5]	2.014[5]	2.115[3]	-
N—C=C—N	1.330[8]	1.341[9]	1.347[4]	-
CCH2−N	1.496[7]	1.456[7]	1.476[3]	-
CCH2−CCpc	1.482[8]	1.498[8]	1.485[4]	-
Fe−CCp	2.013[7]	2.079[6]	2.036[3]	2.095[5]
N−Ccarbene−N	105.0(4)	105.6[4]	105.1[2]
C−Au−C	175.8(2)	175.2(2)	177.2[2]
N-CCH2-Ccp	111.7[4]	112.5[4]	111.1[2]
CTCp-CTCp	3.262	3.401	3.289	3.421
Fe-CTCpd	1.631	1.711	1.644	1.711

^aAverage values are reported when two or more chemically identical interatomic distances or angles are present.

^bUncertainties were computed according to Taylor, J. R. An Introduction to Error Analysis, 2^nd ed.; University Science Books: Sausalito, CA, 1997; pp 73–77. The generated uncertainty numbers are represented within [ ]. Cp = cyclopentadienly; CT = centroid.

^cC_cp represents a carbon atom part of cyclopentadienyl ring that is attached the iron atom.

^dCT_cp represents centroid defined by carbon atoms that constitutes cyclopentadienyl ring.