Structure Data of Free Polyatomic Molecules
701
MW
Tetracarbonyl(η2-ethene)iron
C6H4FeO4
C2v
H
r0
Fe–C(1,2)
Fe–C(ax)
Fe–C(eq)
C(1)=C(2)
C(ax)≡O(ax)
C(eq)≡O(eq)
Fe–M a)
[H]–M b)
C–H
Å
2.117(14)
1.815(2)
1.806(9)
1.419(7)
1.142(3)
1.145(3)
1.995(16)
0.217(2)
1.072(4)
θ0
deg
39.2(5)
175.1(22)
111.7(9)
179.8(29)
179.5(7)
120.6(5)
113.7(6)
103.6(9)
rs
Fe–C(1,2)
Fe–C(ax)
Fe–C(eq)
C(1)=C(2)
C(ax)≡O(ax)
C(eq)≡O(eq)
Fe–M a)
[H]–M b)
C–H
Å
2.105(17)
1.811(1)
1.808(10)
1.412(3)
1.145(2)
1.147(2)
1.983(17)
0.219(3)
1.073(2)
θs
deg
39.2(3)
176.8(13)
111.4(9)
178.2(12)
179.4(5)
120.7(1)
113.3(2)
103.7(10)
Atom
Fe
C(ax)
O(ax)
C(eq)
O(eq)
C(1,2)
H
a0 [Å]
0.0
±1.814
±2.954
0.0
0.0
0.0
±0.897
b0 [Å]
0.0
0.0
0.0
±1.496
±2.448
±0.709
±1.254
C(1)–Fe–C(2)
C(ax)–Fe–C(ax)
C(eq)–Fe–C(eq)
Fe–C(ax)≡O(ax)
Fe–C(eq)≡O(eq)
C=C–H
H–C–H
Fe–C=C–H c)
C(1)–Fe–C(2)
C(ax)–Fe–C(ax)
C(eq)–Fe–C(eq)
Fe–C(ax)≡O(ax)
Fe–C(eq)≡O(eq)
C=C–H
H–C–H
Fe–C=C–H c)
H
H
H
O C Fe C O
C
C
O
O
c0 [Å]
0.073
0.148
0.205
–0.942
–1.576
2.067
2.2835
The ethylene ligand exhibits significant structural changes upon complexation to iron,
primarily an increase in the C–C bond length with movement of the hydrogen atoms
away from the metal center. The plane of the hydrogen atoms is displaced 0.217(2) Å
above the ethylene carbon atoms, along the c axis.
a
) M denotes the center of the C=C bond.
) [H] denotes the plane made by the ethylene hydrogen atoms.
c
) Dihedral angle.
b
Drouin, B.J., Kukolich, S.G.: J. Am. Chem. Soc. 121 (1999) 4023.
II/25D (3, 2168)
Landolt-Börnstein
New Series II/28D