Chemical Compounds
| Formula | color | symmetry | space group | No | Pearson symbol | a (pm) | b (pm) | c (pm) | Z | density, g/cm3 |
|---|---|---|---|---|---|---|---|---|---|---|
| Pa | silvery-gray | tetragonal | I4/mmm | 139 | tI2 | 392.5 | 392.5 | 323.8 | 2 | 15.37 |
| PaO | rocksalt | Fm3m | 225 | cF8 | 496.1 | 4 | 13.44 | |||
| PaO2 | black | fcc | Fm3m | 225 | cF12 | 550.5 | 4 | 10.47 | ||
| Pa2O5 | white | Fm3m | 225 | cF16 | 547.6 | 547.6 | 547.6 | 4 | 10.96 | |
| Pa2O5 | white | orthorhombic | 692 | 402 | 418 | |||||
| PaH3 | black | cubic | Pm3n | 223 | cP32 | 664.8 | 664.8 | 664.8 | 8 | 10.58 |
| PaF4 | brown-red | monoclinic | C2/c | 15 | mS60 | 2 | ||||
| PaCl4 | green-yellow | tetragonal | I41/amd | 141 | tI20 | 837.7 | 837.7 | 748.1 | 4 | 4.72 |
| PaBr4 | brown | tetragonal | I41/amd | 141 | tI20 | 882.4 | 882.4 | 795.7 | ||
| PaCl5 | yellow | monoclinic | C2/c | 15 | mS24 | 797 | 1135 | 836 | 4 | 3.74 |
| PaBr5 | red | monoclinic | P21/c | 14 | mP24 | 838.5 | 1120.5 | 1214.6 | 4 | 4.98 |
| PaOBr3 | monoclinic | C2 | 1691.1 | 387.1 | 933.4 | |||||
| Pa(PO3)4 | orthorhombic | 696.9 | 895.9 | 1500.9 | ||||||
| Pa2P2O7 | cubic | Pa3 | 865 | 865 | 865 | |||||
| Pa(C8H8)2 | golden-yellow | monoclinic | 709 | 875 | 1062 |
Here a, b and c are lattice constants in picometers, No is space group number and Z is the number of formula units per unit cell; fcc stands for the face-centered cubic symmetry. Density was not measured directly but calculated from the lattice parameters.
Read more about this topic: Protactinium
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