Transformation of Ammonium Dicyanamide into Dicyandiamide in the Solid
Barbara Jürgens; Henning A. Höppe; Elisabeth Irran; Wolfgang Schnick; Inorganic Chemistry 41 (2002) 4849–4851; doi:10.1021/ic025800k

data_4318537
_publ_section_title
;
 Transformation of Ammonium Dicyanamide into Dicyandiamide in the Solid
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              4849
_journal_page_last               4851
_journal_paper_doi               10.1021/ic025800k
_journal_volume                  41
_journal_year                    2002
_chemical_formula_sum            'C2 H4 N4'
_chemical_formula_weight         84.09
_chemical_name_common            'ammonium dicyanamide'
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 91.488(18)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   3.7867(6)
_cell_length_b                   12.409(3)
_cell_length_c                   9.1184(14)
_cell_measurement_reflns_used    1313
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      27.5
_cell_measurement_theta_min      2.7
_cell_volume                     428.32(14)
_computing_data_reduction        'X-RED (Stoe, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      200(2)
_diffrn_measured_fraction_theta_full 0.945
_diffrn_measured_fraction_theta_max 0.945
_diffrn_measurement_device_type  'STOE-IPDS diffractometer'
_diffrn_radiation_collimation    '0.5 mm collimator'
_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  0.0604
_diffrn_reflns_av_sigmaI/netI    0.0669
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
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_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            3620
_diffrn_reflns_theta_full        27.89
_diffrn_reflns_theta_max         27.5
_diffrn_reflns_theta_min         2.77
_diffrn_source_current           50_mA
_diffrn_source_power             2.75_kW
_diffrn_source_voltage           55_kV
_exptl_absorpt_coefficient_mu    0.097
_exptl_absorpt_correction_T_max  0.9925
_exptl_absorpt_correction_T_min  0.9507
_exptl_absorpt_correction_type   numerical
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.304
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             176
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.161
_refine_diff_density_min         -0.189
_refine_diff_density_rms         0.049
_refine_ls_extinction_coef       0.042(8)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.816
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_refine_ls_matrix_type           full
_refine_ls_number_parameters     72
_refine_ls_number_reflns         953
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.816
_refine_ls_R_factor_all          0.0775
_refine_ls_R_factor_gt           0.0387
_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/[\s^2^(Fo^2^)+(0.0452P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0807
_refine_ls_wR_factor_ref         0.0893
_reflns_number_gt                534
_reflns_number_total             953
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic025800k_s1.cif
_cod_data_source_block           p:\krist\z144_ip\lsg\g026
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_cell_volume        428.32(13)
_cod_database_code               4318537
_diffrn_detector_area_plate_dist 60.0_mm
_diffrn_detector_area_phi_incr   1.5
_diffrn_detector_area_expos_time 26.00_min
_diffrn_detector_area_profile_min 9
_diffrn_detector_area_profile_max 23
_diffrn_detector_area_phi_start  0.0
_diffrn_detector_area_phi_end    180.0
_diffrn_detector_area_eff_mos_spread 0.005