data_2204347
_publ_section_title
;
 β-Strontium carbodiimide
;
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              i124
_journal_page_last               i126
_journal_paper_doi               10.1107/S1600536804023244
_journal_volume                  60
_journal_year                    2004
_chemical_formula_iupac          'Sr C N2'
_chemical_formula_moiety         'Sr C N2'
_chemical_formula_structural     'Sr C N2'
_chemical_formula_sum            'C N2 Sr'
_chemical_formula_weight         127.65
_chemical_name_systematic
;
β-Strontium cyanamide
;
_space_group_IT_number           166
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3 2"'
_symmetry_space_group_name_H-M   'R -3 m :H'
_atom_sites_solution_primary     isomor
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   3.9732(5)
_cell_length_b                   3.9732(5)
_cell_length_c                   15.028(3)
_cell_measurement_reflns_used    893
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30.25
_cell_measurement_theta_min      4.07
_cell_volume                     205.45(5)
_computing_cell_refinement       SMART
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        'SAINT-Plus (Bruker, 1999)'
_computing_molecular_graphics    'ATOMS (Dowty, 2002)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXTL (Sheldrick, 1998)'
_computing_structure_solution
'atomic coordinates of CaNCN (Vannerberg, 1962) used'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.980
_diffrn_measured_fraction_theta_max 0.980
_diffrn_measurement_device_type  'Bruker SMART APEX CCD'
_diffrn_measurement_method       ω
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0691
_diffrn_reflns_av_sigmaI/netI    0.0415
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            893
_diffrn_reflns_theta_full        30.25
_diffrn_reflns_theta_max         30.25
_diffrn_reflns_theta_min         4.07
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    19.394
_exptl_absorpt_correction_T_max  0.312
_exptl_absorpt_correction_T_min  0.246
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.095
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             174
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.553
_refine_diff_density_min         -0.482
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.068
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     8
_refine_ls_number_reflns         97
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.068
_refine_ls_R_factor_all          0.0174
_refine_ls_R_factor_gt           0.0174
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[σ²(Fo²)+(0.0153P)²] where P = (Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0408
_refine_ls_wR_factor_ref         0.0408
_reflns_number_gt                97
_reflns_number_total             97
_reflns_threshold_expression     I>2σ(I)
_[local]_cod_data_source_file    hb6095.cif
_[local]_cod_data_source_block   I
_[local]_cod_cif_authors_sg_H-M  'R -3 m'
_cod_database_code               2204347
_cod_database_fobs_code          2204347
loop_
_symmetry_equiv_pos_as_xyz
'x, y, z'
'-y, x-y, z'
'-x+y, -x, z'
'y, x, -z'
'x-y, -y, -z'
'-x, -x+y, -z'
'x+2/3, y+1/3, z+1/3'
'-y+2/3, x-y+1/3, z+1/3'
'-x+y+2/3, -x+1/3, z+1/3'
'y+2/3, x+1/3, -z+1/3'
'x-y+2/3, -y+1/3, -z+1/3'
'-x+2/3, -x+y+1/3, -z+1/3'
'x+1/3, y+2/3, z+2/3'
'-y+1/3, x-y+2/3, z+2/3'
'-x+y+1/3, -x+2/3, z+2/3'
'y+1/3, x+2/3, -z+2/3'
'x-y+1/3, -y+2/3, -z+2/3'
'-x+1/3, -x+y+2/3, -z+2/3'
'-x, -y, -z'
'y, -x+y, -z'
'x-y, x, -z'
'-y, -x, z'
'-x+y, y, z'
'x, x-y, z'
'-x+2/3, -y+1/3, -z+1/3'
'y+2/3, -x+y+1/3, -z+1/3'
'x-y+2/3, x+1/3, -z+1/3'
'-y+2/3, -x+1/3, z+1/3'
'-x+y+2/3, y+1/3, z+1/3'
'x+2/3, x-y+1/3, z+1/3'
'-x+1/3, -y+2/3, -z+2/3'
'y+1/3, -x+y+2/3, -z+2/3'
'x-y+1/3, x+2/3, -z+2/3'
'-y+1/3, -x+2/3, z+2/3'
'-x+y+1/3, y+2/3, z+2/3'
'x+1/3, x-y+2/3, z+2/3'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_calc_flag
_atom_site_refinement_flags
_atom_site_occupancy
_atom_site_type_symbol
Sr 0.3333 0.6667 0.1667 0.0145(3) Uani d S 1 Sr
N 0.0000 0.0000 0.0820(3) 0.0182(10) Uani d S 1 N
C 0.0000 0.0000 0.0000 0.0126(14) Uani d S 1 C
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Sr 0.0131(3) 0.0131(3) 0.0172(4) 0.00654(15) 0.000 0.000
N 0.0179(16) 0.0179(16) 0.019(2) 0.0089(8) 0.000 0.000
C 0.009(2) 0.009(2) 0.020(4) 0.0044(10) 0.000 0.000
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
N N 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Sr Sr -1.5307 3.2498 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_3
_geom_angle
_geom_angle_publ_flag
N Sr N 1_565 . 98.45(11) yes
N Sr N 1_565 25 180 yes
N Sr N . 25 81.55(11) yes
N Sr N 1_565 1_665 98.45(11) no
N Sr N . 1_665 98.45(11) no
N Sr N 25 1_665 81.55(11) no
N Sr N 1_565 25_565 81.55(11) no
N Sr N . 25_565 180.0 no
N Sr N 25 25_565 98.45(11) no
N Sr N 1_665 25_565 81.55(11) no
N Sr N 1_565 25_455 81.55(11) no
N Sr N . 25_455 81.55(11) no
N Sr N 25 25_455 98.45(11) no
N Sr N 1_665 25_455 180.0 no
N Sr N 25_565 25_455 98.45(11) no
C N Sr . 1_545 119.02(9) yes
C N Sr . . 119.02(9) no
Sr N Sr 1_545 . 98.45(11) yes
C N Sr . 1_445 119.02(9) no
Sr N Sr 1_545 1_445 98.45(11) no
Sr N Sr . 1_445 98.45(11) no
N C N 19 . 180 yes
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_site_symmetry_2
_geom_bond_distance
_geom_bond_publ_flag
Sr N . 2.623(2) yes
Sr N 1_565 2.623(2) no
Sr N 25 2.623(2) no
Sr N 1_665 2.623(2) no
Sr N 25_565 2.623(2) no
Sr N 25_455 2.623(2) no
N C . 1.232(5) yes
N Sr 1_545 2.623(2) no
N Sr 1_445 2.623(2) no
C N 19 1.232(5) no
