Synthesis, Structure, and Infrared Spectroscopy of the First Np5+ Neptunyl Silicates, Li6(NpO2)4(H2Si2O7)(HSiO4)2(H2O)4 and K3(NpO2)3(Si2O7)
T. Z. Forbes; P. C. Burns; Inorganic Chemistry 47 (2008) 705–712; doi:10.1021/ic701335j

data_4304042
_publ_contact_author_address
;University of Notre Dame
Dept. of Civil Engineering and Geosciences
156 Fitzpatrick Hall
Notre Dame, IN 46556
;
_publ_contact_author_email       pburns@nd.edu
_publ_contact_author_name        'Peter C. Burns'
_publ_contact_author_phone       574-631-7216
_publ_section_title
;
Synthesis, Structure, and Infrared Spectroscopy of the First Np5+ Neptunyl
Silicates, Li6(NpO2)4(H2Si2O7)(HSiO4)2(H2O)4 and K3(NpO2)3(Si2O7)
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              705
_journal_page_last               712
_journal_paper_doi               10.1021/ic701335j
_journal_volume                  47
_journal_year                    2008
_chemical_formula_moiety         ' Np3 Si2 O13 3(K)'
_chemical_formula_sum            'K Np O4.33 Si0.67'
_chemical_formula_weight         364.20
_chemical_name_common            'potassium neptunyl silicate'
_chemical_name_systematic        'potassium neptunyl silicate'
_space_group_IT_number           189
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  'P -6 -2'
_symmetry_space_group_name_H-M   'P -6 2 m'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   9.7337(13)
_cell_length_b                   9.7337(13)
_cell_length_c                   3.8817(7)
_cell_measurement_temperature    293(2)
_cell_volume                     318.50(8)
_computing_cell_refinement       'APEX II Software'
_computing_data_collection       'APEX II Software'
_computing_data_reduction        'APEX II Software'
_computing_molecular_graphics    'CrystalMaker v 1.3.1'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.990
_diffrn_measurement_device_type  'Bruker XRD w/ APEX II CCD detector'
_diffrn_measurement_method       \w
_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  0.0964
_diffrn_reflns_av_sigmaI/netI    0.0452
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            6548
_diffrn_reflns_theta_full        34.60
_diffrn_reflns_theta_max         34.60
_diffrn_reflns_theta_min         2.42
_exptl_absorpt_coefficient_mu    25.534
_exptl_absorpt_correction_T_max  0.572
_exptl_absorpt_correction_T_min  0.457
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   'modeled as an ellipsoid using XPREP'
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    5.780
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             476
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.01
_exptl_crystal_size_min          0.01
_refine_diff_density_max         1.519
_refine_diff_density_min         -2.492
_refine_diff_density_rms         0.317
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.05(7)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.081
_refine_ls_matrix_type           full
_refine_ls_number_parameters     20
_refine_ls_number_reflns         544
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.081
_refine_ls_R_factor_all          0.0363
_refine_ls_R_factor_gt           0.0339
_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^)+(0.0202P)^2^+1.1581P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0564
_refine_ls_wR_factor_ref         0.0568
_reflns_number_gt                527
_reflns_number_total             544
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic701335j-file002.cif
_cod_data_source_block           pcb
_cod_database_code               4304042