The compound described by Ca(AlH4)2 crystallizes in the hexagonal P-62m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to three equivalent H(5) and six equivalent H(3) atoms. In the second Ca site, Ca(2) is bonded in a 9-coordinate geometry to three equivalent H(1) and six equivalent H(6) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one H(3), two equivalent H(1), and two equivalent H(2) atoms to form corner-sharing AlH5 trigonal bipyramids. In the second Al site, Al(2) is bonded to one H(5), two equivalent H(4), and two equivalent H(6) atoms to form corner-sharing AlH5 trigonal bipyramids. There are six inequivalent H sites. In the first H site, H(1) is bonded in a distorted bent 150 degrees geometry to one Ca(2) and one Al(1) atom. In the second H site, H(2) is bonded in a linear geometry to two equivalent Al(1) atoms. In the third H site, H(3) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one Al(1) atom. In the fourth H site, H(4) is bonded in a linear geometry to two equivalent Al(2) atoms. In the fifth H site, H(5) is bonded in a distorted linear geometry to one Ca(1) and one Al(2) atom. In the sixth H site, H(6) is bonded in a 3-coordinate geometry to two equivalent Ca(2) and one Al(2) atom. is represented by the CIF card [CIF]
data_Ca(AlH4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.600
_cell_length_b   10.375
_cell_length_c   10.375
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   335.612
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.500  0.667  0.333  1.0
  Ca  Ca2  1  0.500  0.333  0.667  1.0
  Al  Al3  1  0.500  0.718  0.718  1.0
  Al  Al4  1  0.500  0.000  0.282  1.0
  Al  Al5  1  0.500  0.282  0.000  1.0
  Al  Al6  1  0.000  0.389  0.389  1.0
  Al  Al7  1  0.000  0.000  0.611  1.0
  Al  Al8  1  0.000  0.611  0.000  1.0
  H  H9  1  0.500  0.840  0.272  1.0
  H  H10  1  0.500  0.431  0.160  1.0
  H  H11  1  0.500  0.569  0.728  1.0
  H  H12  1  0.500  0.728  0.569  1.0
  H  H13  1  0.500  0.272  0.840  1.0
  H  H14  1  0.500  0.160  0.431  1.0
  H  H15  1  0.000  0.729  0.729  1.0
  H  H16  1  0.000  0.000  0.271  1.0
  H  H17  1  0.000  0.271  0.000  1.0
  H  H18  1  0.500  0.876  0.876  1.0
  H  H19  1  0.500  0.000  0.124  1.0
  H  H20  1  0.500  0.124  0.000  1.0
  H  H21  1  0.500  0.409  0.409  1.0
  H  H22  1  0.500  0.000  0.591  1.0
  H  H23  1  0.500  0.591  0.000  1.0
  H  H24  1  0.000  0.233  0.233  1.0
  H  H25  1  0.000  0.000  0.767  1.0
  H  H26  1  0.000  0.767  0.000  1.0
  H  H27  1  0.000  0.834  0.454  1.0
  H  H28  1  0.000  0.621  0.166  1.0
  H  H29  1  0.000  0.379  0.546  1.0
  H  H30  1  0.000  0.546  0.379  1.0
  H  H31  1  0.000  0.454  0.834  1.0
  H  H32  1  0.000  0.166  0.621  1.0
[/CIF]
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The compound described by Ca(AlH4)2 crystallizes in the hexagonal P-62m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to three equivalent H(5) and six equivalent H(3) atoms. In the second Ca site, Ca(2) is bonded in a 9-coordinate geometry to three equivalent H(1) and six equivalent H(6) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one H(3), two equivalent H(1), and two equivalent H(2) atoms to form corner-sharing AlH5 trigonal bipyramids. In the second Al site, Al(2) is bonded to one H(5), two equivalent H(4), and two equivalent H(6) atoms to form corner-sharing AlH5 trigonal bipyramids. There are six inequivalent H sites. In the first H site, H(1) is bonded in a distorted bent 150 degrees geometry to one Ca(2) and one Al(1) atom. In the second H site, H(2) is bonded in a linear geometry to two equivalent Al(1) atoms. In the third H site, H(3) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one Al(1) atom. In the fourth H site, H(4) is bonded in a linear geometry to two equivalent Al(2) atoms. In the fifth H site, H(5) is bonded in a distorted linear geometry to one Ca(1) and one Al(2) atom. In the sixth H site, H(6) is bonded in a 3-coordinate geometry to two equivalent Ca(2) and one Al(2) atom. is represented by the CIF card [CIF]
data_Ca(AlH4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.600
_cell_length_b   10.375
_cell_length_c   10.375
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   335.612
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.500  0.667  0.333  1.0
  Ca  Ca2  1  0.500  0.333  0.667  1.0
  Al  Al3  1  0.500  0.718  0.718  1.0
  Al  Al4  1  0.500  0.000  0.282  1.0
  Al  Al5  1  0.500  0.282  0.000  1.0
  Al  Al6  1  0.000  0.389  0.389  1.0
  Al  Al7  1  0.000  0.000  0.611  1.0
  Al  Al8  1  0.000  0.611  0.000  1.0
  H  H9  1  0.500  0.840  0.272  1.0
  H  H10  1  0.500  0.431  0.160  1.0
  H  H11  1  0.500  0.569  0.728  1.0
  H  H12  1  0.500  0.728  0.569  1.0
  H  H13  1  0.500  0.272  0.840  1.0
  H  H14  1  0.500  0.160  0.431  1.0
  H  H15  1  0.000  0.729  0.729  1.0
  H  H16  1  0.000  0.000  0.271  1.0
  H  H17  1  0.000  0.271  0.000  1.0
  H  H18  1  0.500  0.876  0.876  1.0
  H  H19  1  0.500  0.000  0.124  1.0
  H  H20  1  0.500  0.124  0.000  1.0
  H  H21  1  0.500  0.409  0.409  1.0
  H  H22  1  0.500  0.000  0.591  1.0
  H  H23  1  0.500  0.591  0.000  1.0
  H  H24  1  0.000  0.233  0.233  1.0
  H  H25  1  0.000  0.000  0.767  1.0
  H  H26  1  0.000  0.767  0.000  1.0
  H  H27  1  0.000  0.834  0.454  1.0
  H  H28  1  0.000  0.621  0.166  1.0
  H  H29  1  0.000  0.379  0.546  1.0
  H  H30  1  0.000  0.546  0.379  1.0
  H  H31  1  0.000  0.454  0.834  1.0
  H  H32  1  0.000  0.166  0.621  1.0
[/CIF]
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