Table 1. Selected interatomic distances for complexes 2 to 7 in Å given as ranges and averages due to multiple cationic moieties in the asymmetric unit together with bond valences {v.u.}, according to I.D. Brown for complexes 3 to 7.19 Al–Oavg. for O atoms showing no interaction to the central AE element.
M= | 2 | 3 | 4 | 5 | 6 | 7 | |
Ca | Ca | Ba | Sr | Sr | Ca | ||
HMB | M–Crange | 2.82(1)–2.88(1) | 2.787(9)–2.906(9) | 3.134(7)–3.193(7) | 2.997(6)–3.016(6) | 2.997(3)–3.025(3) | 2.813(3)–2.916(3) |
M–Cavg. | 2.84(1) | 2.843(9) | 3.170(7) | 3.006(5) | 3.015(3) | 2.872(3) | |
oDFB | M–Frange | 2.415(7)–2.483(7) | 2.445(6)–2.503(6) | 2.791(4)–2.939(5) | 2.625(3)–2.703(3) | 2.595(2)–2.799(2) | 2.360(2)–2.565(2) |
{0.17–0.20; Σ = 0.72} | {0.11–0.20; Σ = 0.83} | {0.15–0.20; Σ = 1.03} | {0.15–0.21; Σ = 1.35} | {0.14–0.25; Σ = 1.13} | |||
M–Favg. | 2.441(7) | 2.471(6) | 2.865(4) | 2.661(3) | 2.683(2) | 2.466(2) | |
C–Frange | 1.36(1)–1.39(1) | 1.376(3)–1.379(3) | 1.364(9)–1.389(9) | 1.362(5)–1.393(5) | 1.376(2)–1.386(2) | 1.371(3)–1.392(3) | |
C–Favg. | 1.38(1) | 1.378(3) | 1.378(9) | 1.375(5) | 1.381(2) | 1.381(3) | |
[f-al]– | M–F | 2.185(7) | 2.189(6) | 2.589(4) | 2.338(3) | — | — |
{0.39} | {0.34} | {0.42} | |||||
Al–F | 1.714(8) | 1.712(6) | 1.705(4) | 1.699(3) | — | — | |
{0.64} | {0.65} | {0.66} | |||||
M–O | — | 3.05(2) | 2.941(5) | — | — | — | |
{0.05} | {0.17} | ||||||
Al–Oavg. | 1.704(9) | 1.69(2) | 1.709(5) | 1.70(1) | — | — | |
Al–OM bound | — | 1.77(2) | 1.769(5) | — | — | — |