Selected bond lengths and prism heights h (both in Å) in compounds 3–6. Additional bond lengths are presented in the ESI.
| 3 | 4 | 5 | 6 | |
|---|---|---|---|---|
| h 1 | 3.976(1) | 3.918(1) | 3.429(1) | 3.370(1) |
| h 2 | 2.759(2) | 2.815(2) | 3.525(1) | 3.663(1) |
| h 3 | 2.932(1) | 2.934(1) | 3.295(1) | 3.201(1) |
| h long/hshort | 1.44 | 1.39 | 1.07 | 1.14 |
| Ge–Geshort | 2.5038(8) (Ge1–Ge2) | 2.5046(8) (Ge1–Ge2) | 2.5031(9) (Ge6–Ge9) | 2.5128(7) (Ge3–Ge7) |
| Ge–Gelong | 2.9322(8) (Ge7–Ge8) | 2.9324(8) (Ge7–Ge8) | 2.715(1) (Ge4–Ge8) | 2.7396(7) (Ge4–Ge8) |
| Ge1–C1 | 1.995(5) | 2.007(5) | 1.984(6) | 1.997(4) |
| Ge3–Si1 | 2.396(2) | 2.392(2) | 2.381(2) | 2.369(1) |
| Ge5–Si5 or Ge9–Si5 | 2.395(2) | 2.403(2) | 2.383(2) | 2.381(1) |