Table 1. Selected interatomic distances [Å] in the molecular structures of the siliconoid anions 1b, 2b and 3b from single crystal structure determinations (molecular structures with atom labelling in Fig. 3 and 4).
| Bond type | {Si(TMS)3}2Si92– (1b) | (SiHtBu2)2Si92– (3b)30 | (SnCy3)2Si92– (2b) |
| Exo-bonds | Si1–Si10: 2.357(5) | Si1–Si10: 2.349(2) | Si1–Sn: 2.578(1) |
| Si3–Si14: 2.339(5) | Si3–Si11: 2.379(2) | Si1′–Sn′: 2.578(1) | |
| Type 1 | Si1–Si2: 2.396(5) | Si1–Si2: 2.405(2) | Si1–Si2: 2.430(2) |
| Si1–Si4: 2.427(5) | Si1–Si4: 2.423(2) | Si1–Si2′: 2.433(2) | |
| Si2–Si3: 2.395(4) | Si2–Si3: 2.418(2) | Si1′–Si2: 2.433(2) | |
| Si3–Si4: 2.398(5) | Si3–Si4: 2.414(2) | Si1′–Si2′: 2.430(2) | |
| Si5–Si9: 2.468(6) | Si5–Si9: 2.429(2) | Si4–Si5: 2.436(2) | |
| Si6–Si9: 2.470(6) | Si6–Si9: 2.441(2) | Si3–Si5: 2.432(2) | |
| Si7–Si9: 2.427(6) | Si7–Si9: 2.450(2) | Si4′–Si5: 2.436(2) | |
| Si8–Si9: 2.475(7) | Si8–Si9: 2.447(2) | Si3′–Si5: 2.432(2) | |
| Type 2 | Si5–Si6: 2.772(6) | Si5–Si6: 2.782(2) | Si3–Si4: 2.664(2) |
| Si7–Si8: 2.738(5) | Si7–Si8: 2.764(2) | Si3′–Si4′: 2.664(2) | |
| Si6–Si7: 2.569(6) | Si6–Si7: 2.534(2) | Si3–Si4′: 2.565(2) | |
| Si5–Si8: 2.585(6) | Si5–Si8: 2.534(2) | Si3′–Si4: 2.565(2) |