data_Mg2C3
_chemical_name_systematic 'Magnesium carbide (2/3)'
_chemical_formula_structural 'Mg2 C3'
_chemical_formula_sum 'C3 Mg2'
_exptl_crystal_density_diffrn 2.23
_publ_section_title 'Crystal structure of magnesium sesquicarbide'
loop_
_citation_id
_citation_journal_full
_citation_year
_citation_journal_volume
_citation_page_first
_citation_page_last
_citation_journal_id_ASTM
primary 'Inorganic Chemistry' 1992 31 3260 3263 INOCAJ
loop_
_publ_author_name
'Fjellvag, H.'
'Karen, P.'
_cell_length_a 6.4108(3)
_cell_length_b 5.2786(2)
_cell_length_c 3.7283(2)
_cell_angle_alpha 90.
_cell_angle_beta 90.
_cell_angle_gamma 90.
_cell_volume 126.17
_cell_formula_units_Z 2
_symmetry_space_group_name_H-M 'P n n m'
_symmetry_Int_Tables_number 58
_refine_ls_R_factor_all 0.069
loop_
_symmetry_equiv_pos_site_id
_symmetry_equiv_pos_as_xyz
1 'x+1/2, -y+1/2, z+1/2'
2 '-x+1/2, y+1/2, z+1/2'
3 'x, y, -z'
4 '-x, -y, -z'
5 '-x+1/2, y+1/2, -z+1/2'
6 'x+1/2, -y+1/2, -z+1/2'
7 '-x, -y, z'
8 'x, y, z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
Mg0+ 0
C0+ 0
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_B_iso_or_equiv
_atom_site_occupancy
_atom_site_attached_hydrogens
Mg1 Mg0+ 4 g 0.2903(3) 0.3901(4) 0 . 1. 0
C1 C0+ 2 d 0.5 0 0 1.02(4) 1. 0
C2 C0+ 4 g 0.6188(3) 0.2070(3) 0 . 1. 0
loop_
_atom_site_aniso_label
_atom_site_aniso_type_symbol
_atom_site_aniso_B_11
_atom_site_aniso_B_22
_atom_site_aniso_B_33
_atom_site_aniso_B_12
_atom_site_aniso_B_13
_atom_site_aniso_B_23
Mg1 Mg0+ 1.28(12) 0.59(8) 1.02(8) -.01(6) 0 0
C2 C0+ 0.60(6) 0.36(5) 1.14(6) -.03(5) 0 0