#------------------------------------------------------------------------------
#$Date: 2016-02-21 01:03:34 +0100 (dom 21 de feb de 2016) $
#$Revision: 176798 $
#$URL: svn://www.crystallography.net/cod/cif/2/23/09/2230972.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided by IUCr Journals, http://journals.iucr.org/.
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_2230972
loop_
_publ_author_name
'Jaemin Yu'
'Hoseop Yun'
_publ_section_title
;
 Reinvestigation of the low-temperature form of Ag₂Se (naumannite) based
 on single-crystal data
;
_journal_coeditor_code           WM2506
_journal_issue                   9
_journal_name_full               'Acta Crystallographica, Section E'
_journal_page_first              i45
_journal_page_last               i45
_journal_paper_doi               10.1107/S1600536811028534
_journal_volume                  67
_journal_year                    2011
_chemical_formula_iupac          'Ag2 Se'
_chemical_formula_moiety         'Ag2 Se'
_chemical_formula_sum            'Ag2 Se'
_chemical_formula_weight         294.7
_chemical_name_systematic
;
disilver(I) selenide
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   4.3359(8)
_cell_length_b                   7.0700(10)
_cell_length_c                   7.7740(10)
_cell_measurement_reflns_used    1738
_cell_measurement_temperature    290.0(10)
_cell_measurement_theta_max      27.50
_cell_measurement_theta_min      3.40
_cell_volume                     238.31(6)
_computing_cell_refinement       'RAPID-AUTO (Rigaku, 2006)'
_computing_data_collection       'RAPID-AUTO (Rigaku, 2006)'
_computing_data_reduction        'RAPID-AUTO (Rigaku, 2006)'
_computing_molecular_graphics
'locally modified version of ORTEP (Johnson, 1965)'
_computing_publication_material  'WinGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      290.0(10)
_diffrn_measured_fraction_theta_full 1
_diffrn_measured_fraction_theta_max 1
_diffrn_measurement_device_type  'Rigaku R-AXIS RAPID'
_diffrn_measurement_method       ω
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.057
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            1981
_diffrn_reflns_theta_full        25.99
_diffrn_reflns_theta_max         25.99
_diffrn_reflns_theta_min         3.9
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    31.267
_exptl_absorpt_correction_T_max  0.278
_exptl_absorpt_correction_T_min  0.053
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(NUMABS; Higashi, 2000)'
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    8.213
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             512
_exptl_crystal_size_max          0.300
_exptl_crystal_size_mid          0.040
_exptl_crystal_size_min          0.020
_refine_diff_density_max         1.192
_refine_diff_density_min         -1.069
_refine_ls_abs_structure_details 'Flack (1983), 167 Friedel pairs'
_refine_ls_abs_structure_Flack   0.34(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.135
_refine_ls_matrix_type           full
_refine_ls_number_parameters     29
_refine_ls_number_reflns         464
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.135
_refine_ls_R_factor_gt           0.0311
_refine_ls_shift/su_max          0
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[σ²(Fo²)+(0.0329P)²+1.0072P] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.0799
_reflns_number_gt                447
_reflns_number_total             464
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            wm2506.cif
_cod_data_source_block           I
_cod_original_cell_volume        238.34(7)
_cod_database_code               2230972
_cod_database_fobs_code          2230972
loop_
_symmetry_equiv_pos_as_xyz
'x, y, z'
'-x+1/2, -y, z+1/2'
'x+1/2, -y+1/2, -z'
'-x, y+1/2, -z+1/2'
loop_
_atom_site_type_symbol
_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_disorder_assembly
_atom_site_disorder_group
Ag Ag1 0.8537(2) 0.11503(14) 0.45100(14) 0.0398(3) Uani d . 1 . .
Ag Ag2 0.4745(3) 0.77441(14) 0.36152(14) 0.0447(4) Uani d . 1 . .
Se Se 0.1124(2) 0.99787(14) 0.15274(14) 0.0242(3) Uani d . 1 . .
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
Ag1 0.0381(6) 0.0378(6) 0.0436(6) -0.0010(5) 0.0080(5) 0.0060(4)
Ag2 0.0462(7) 0.0338(6) 0.0540(7) 0.0131(4) -0.0100(5) -0.0057(5)
Se 0.0249(5) 0.0190(6) 0.0286(6) 0.0001(4) -0.0011(4) -0.0006(4)
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
Ag Ag -0.897 1.102 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Se Se -0.093 2.226 '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
Se Ag1 Se 2_565 1_645 136.30(5) ?
Se Ag1 Se 2_565 4_645 119.41(5) ?
Se Ag1 Se 1_645 4_645 91.55(3) ?
Se Ag1 Se 2_565 2_665 101.71(5) ?
Se Ag1 Se 1_645 2_665 92.76(3) ?
Se Ag1 Se 4_645 2_665 112.04(5) ?
Se Ag2 Se 4_645 4_545 94.87(4) ?
Se Ag2 Se . 4_545 82.95(3) ?
Se Ag2 Se 2_575 4_545 105.72(5) ?
Se Ag1 Ag1 2_565 3_556 126.05(6) ?
Se Ag1 Ag1 1_645 3_556 96.50(4) ?
Se Ag1 Ag1 4_645 3_556 54.80(4) ?
Se Ag1 Ag1 2_665 3_556 57.32(3) ?
Se Ag1 Ag1 2_565 3_456 59.58(3) ?
Se Ag1 Ag1 1_645 3_456 135.65(6) ?
Se Ag1 Ag1 4_645 3_456 59.92(5) ?
Se Ag1 Ag1 2_665 3_456 127.99(6) ?
Ag1 Ag1 Ag1 3_556 3_456 93.06(6) ?
Se Ag1 Ag2 2_565 1_545 58.86(4) ?
Se Ag1 Ag2 1_645 1_545 77.44(4) ?
Se Ag1 Ag2 4_645 1_545 136.98(5) ?
Se Ag1 Ag2 2_665 1_545 109.95(4) ?
Ag1 Ag1 Ag2 3_556 1_545 166.05(5) ?
Ag1 Ag1 Ag2 3_456 1_545 100.04(3) ?
Se Ag1 Ag2 2_565 4_645 103.04(4) ?
Se Ag1 Ag2 1_645 4_645 67.77(4) ?
Se Ag1 Ag2 4_645 4_645 55.96(3) ?
Se Ag1 Ag2 2_665 4_645 155.18(5) ?
Ag1 Ag1 Ag2 3_556 4_645 107.91(5) ?
Ag1 Ag1 Ag2 3_456 4_645 68.06(4) ?
Ag2 Ag1 Ag2 1_545 4_645 81.67(3) ?
Se Ag1 Ag2 2_565 3_556 66.13(4) ?
Se Ag1 Ag2 1_645 3_556 93.43(4) ?
Se Ag1 Ag2 4_645 3_556 163.17(5) ?
Se Ag1 Ag2 2_665 3_556 51.68(3) ?
Ag1 Ag1 Ag2 3_556 3_556 108.60(5) ?
Ag1 Ag1 Ag2 3_456 3_556 124.02(5) ?
Ag2 Ag1 Ag2 1_545 3_556 59.85(3) ?
Ag2 Ag1 Ag2 4_645 3_556 140.46(4) ?
Se Ag1 Ag2 2_565 2_665 71.43(4) ?
Se Ag1 Ag2 1_645 2_665 142.30(5) ?
Se Ag1 Ag2 4_645 2_665 92.10(4) ?
Se Ag1 Ag2 2_665 2_665 51.45(3) ?
Ag1 Ag1 Ag2 3_556 2_665 56.62(4) ?
Ag1 Ag1 Ag2 3_456 2_665 76.74(5) ?
Ag2 Ag1 Ag2 1_545 2_665 121.83(4) ?
Ag2 Ag1 Ag2 4_645 2_665 140.93(4) ?
Ag2 Ag1 Ag2 3_556 2_665 74.25(3) ?
Se Ag2 Se 4_645 . 141.46(5) ?
Se Ag2 Se 4_645 2_575 123.20(5) ?
Se Ag2 Se . 2_575 94.00(3) ?
Se Ag2 Ag1 4_645 1_565 103.38(5) ?
Se Ag2 Ag1 . 1_565 89.34(4) ?
Se Ag2 Ag1 2_575 1_565 54.90(4) ?
Se Ag2 Ag1 4_645 4_655 90.54(4) ?
Se Ag2 Ag1 . 4_655 58.26(4) ?
Se Ag2 Ag1 2_575 4_655 142.86(5) ?
Ag1 Ag2 Ag1 1_565 4_655 137.88(5) ?
Se Ag2 Ag2 4_645 3_566 58.04(3) ?
Se Ag2 Ag2 . 3_566 151.45(6) ?
Se Ag2 Ag2 2_575 3_566 66.03(5) ?
Ag1 Ag2 Ag2 1_565 3_566 62.68(4) ?
Ag1 Ag2 Ag2 4_655 3_566 148.22(5) ?
Se Ag2 Ag2 4_645 3_466 114.98(6) ?
Se Ag2 Ag2 . 3_466 94.31(4) ?
Se Ag2 Ag2 2_575 3_466 53.43(4) ?
Ag1 Ag2 Ag2 1_565 3_466 108.32(6) ?
Ag1 Ag2 Ag2 4_655 3_466 100.86(4) ?
Ag2 Ag2 Ag2 3_566 3_466 89.67(6) ?
Se Ag2 Ag1 4_645 3_456 59.27(4) ?
Se Ag2 Ag1 . 3_456 132.61(5) ?
Se Ag2 Ag1 2_575 3_456 96.07(5) ?
Ag1 Ag2 Ag1 1_565 3_456 133.16(4) ?
Ag1 Ag2 Ag1 4_655 3_456 88.17(3) ?
Ag2 Ag2 Ag1 3_566 3_456 72.30(4) ?
Ag2 Ag2 Ag1 3_466 3_456 57.47(4) ?
Se Ag2 Ag1 4_645 2_664 88.98(4) ?
Se Ag2 Ag1 . 2_664 55.60(4) ?
Se Ag2 Ag1 2_575 2_664 131.41(5) ?
Ag1 Ag2 Ag1 1_565 2_664 84.96(4) ?
Ag1 Ag2 Ag1 4_655 2_664 55.32(3) ?
Ag2 Ag2 Ag1 3_566 2_664 122.24(4) ?
Ag2 Ag2 Ag1 3_466 2_664 147.69(4) ?
Ag1 Ag2 Ag1 3_456 2_664 132.52(4) ?
Ag2 Se Ag1 4_655 2_564 134.75(5) ?
Ag2 Se Ag1 4_655 1_465 95.17(4) ?
Ag1 Se Ag1 2_564 1_465 106.26(4) ?
Ag2 Se Ag2 4_655 . 93.59(4) ?
Ag1 Se Ag2 2_564 . 127.12(5) ?
Ag1 Se Ag2 1_465 . 84.66(5) ?
Ag2 Se Ag2 4_655 2_574 68.53(4) ?
Ag1 Se Ag2 2_564 2_574 66.24(4) ?
Ag1 Se Ag2 1_465 2_574 117.42(5) ?
Ag2 Se Ag2 . 2_574 151.82(5) ?
Ag2 Se Ag1 4_655 4_655 131.16(5) ?
Ag1 Se Ag1 2_564 4_655 65.62(4) ?
Ag1 Se Ag1 1_465 4_655 123.98(5) ?
Ag2 Se Ag1 . 4_655 65.78(4) ?
Ag2 Se Ag1 2_574 4_655 109.05(5) ?
Ag2 Se Ag1 4_655 2_664 69.05(4) ?
Ag1 Se Ag1 2_564 2_664 101.71(5) ?
Ag1 Se Ag1 1_465 2_664 151.20(5) ?
Ag2 Se Ag1 . 2_664 72.95(4) ?
Ag2 Se Ag1 2_574 2_664 80.16(4) ?
Ag1 Se Ag1 4_655 2_664 62.75(4) ?
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
Ag1 Se 2_565 2.6800(14) y
Ag1 Se 1_645 2.7058(16) y
Ag1 Se 4_645 2.8282(14) y
Ag1 Se 2_665 2.9076(16) y
Ag1 Ag1 3_556 2.9872(15) ?
Ag1 Ag1 3_456 2.9872(15) ?
Ag1 Ag2 1_545 2.9979(15) ?
Ag1 Ag2 4_645 3.0330(14) ?
Ag1 Ag2 3_556 3.1591(16) ?
Ag1 Ag2 2_665 3.3692(17) ?
Ag2 Se 4_645 2.6538(14) y
Ag2 Se . 2.7560(15) y
Ag2 Se 2_575 2.8036(16) y
Ag2 Se 4_545 3.2112(16) y
Ag2 Ag1 1_565 2.9979(16) ?
Ag2 Ag1 4_655 3.0330(14) ?
Ag2 Ag2 3_566 3.0749(16) ?
Ag2 Ag2 3_466 3.0749(16) ?
Ag2 Ag1 3_456 3.1591(16) ?
Ag2 Ag1 2_664 3.3692(17) ?
Se Ag2 4_655 2.6538(14) ?
Se Ag1 2_564 2.6800(14) ?
Se Ag1 1_465 2.7058(16) ?
Se Ag2 2_574 2.8036(16) ?
Se Ag1 4_655 2.8282(14) ?
Se Ag1 2_664 2.9076(16) ?
