Table 4. Calculated and experimental structural data for the E{N(SiMe₃)₂}₂ (E = Ge, Sn, or Pb) monomers.

Ge{N(SiMe3)2}2
	B3PW91	B3PW91-D3	B97-D3	GED a	X-ray b
E–N (Å)	1.897 (avg.)	1.897	1.909	1.89(1)	1.875(3)
N–Si (Å)	1.778 (avg.)	1.765 (avg.)	1.780 (avg.)	1.743 (avg.)	1.752 (avg.)
N–E–N (°)	107.8	104.3 (avg.)	105.0	101(1.5)	107.1(4)
E–N–Si (°)	117.0 (avg.)	118.9 (avg.)	119.0 (avg.)	121.1 (avg.)	112.6(4)
					124.9(5)

Sn{N(SiMe3)2}2
	B3PW91	B3PW91-D3	B97-D3	GED b	X-ray c
E–N (Å)	2.110	2.093	2.121	2.09 (avg.)	2.092(4)
					(2.096, 2.088)
N–Si (Å)	1.765 (avg.)	1.755 (avg.)	1.769 (avg.)	1.74	1.742
N–E–N (°)	106.4	102.0	102.7	91.2	104.7(2)
E–N–Si (°)	118.3 (avg.)	118.9 (avg.)	118.8 (avg.)	117.3	112.71(4)
					112.9(1)

Pb{N(SiMe3)2}2
	B3PW91	B3PW91-D3	B97-D3	GED c	X-ray c
E–N (Å)	2.251	2.222	2.241	2.20(2)	2.24(2) (avg.)
					(2.260, 2.222)
N–Si (Å)	1.753	1.744 (avg.)	1.759 (avg.)	1.75 (avg.)	1.724 (avg.)
N–E–N (°)	106.5	101.3	101.8	91(2)	103.6(7)
E–N–Si (°)	117.9 (avg.)	118.5	118.5	119.6 (avg.)	112(1)
					120.2(5)

^a Ref. 7.

^b Ref. 4 and 5.

^c Ref. 5.