Table 8.

Effect of different alkali cations on N₂ activation by β-diketiminate iron complexes [116].

Complex	N-N bond distance (Å)	νNN (cm−1)	cation-N distances (Å)	δ (mm/s)	|ΔEQ| (mm/s)
42-Na	1.254(6)	1612	2.51(7)*	0.44	2.52
42-K	1.215(6)	1625	2.78(4)*	0.47	2.48
42-Rb	1.257(6)	1621	2.91(5)*	0.46	2.34
42-Cs	1.33(2)	1613	3.09(2)*	0.48	2.20

^*Denotes average of distances