Selective recognition and binding of arsenate over phosphate
Egdal, Rune Kirk; Raber, Georg; Bond, Andrew D.; Hussain, Munawar; Espino, Maria P. B.; Francesconi, Kevin A.; McKenzie, Christine J.; Dalton Transactions  (2009) 9718–9721; doi:10.1039/b918143c

data_7002819
_publ_section_title
;
 Selective recognition and binding of arsenate over phosphate
;
_journal_issue                   44
_journal_name_full               'Dalton Transactions'
_journal_page_first              9718
_journal_page_last               9721
_journal_paper_doi               10.1039/b918143c
_journal_year                    2009
_chemical_formula_moiety         'C48 H49 N6 O7 P V2 +, 2(Cl O4 -)'
_chemical_formula_sum            'C48 H49 Cl2 N6 O15 P V2'
_chemical_formula_weight         1153.68
_space_group_IT_number           148
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3'
_symmetry_space_group_name_H-M   'R -3 :H'
_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                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            18
_cell_length_a                   34.3754(12)
_cell_length_b                   34.3754(12)
_cell_length_c                   24.9569(7)
_cell_measurement_reflns_used    9617
_cell_measurement_temperature    180(2)
_cell_measurement_theta_max      27.00
_cell_measurement_theta_min      2.37
_cell_volume                     25539.8(15)
_computing_cell_refinement       'SAINT v.7.06a (Bruker, 2003)'
_computing_data_collection       'APEX2 v.1.0-22 (Bruker Nonius, 2004)'
_computing_data_reduction        'SAINT v.7.06a'
_computing_molecular_graphics    'SHELXTL v.6.10'
_computing_publication_material  'SHELXTL v.6.10'
_computing_structure_refinement  'SHELXTL v.6.10'
_computing_structure_solution    'SHELXTL v.6.10 (Sheldrick, 2000)'
_diffrn_ambient_temperature      180(2)
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'Bruker-Nonius X8APEX-II CCD'
_diffrn_measurement_method       'thin-slice \w and \f scans'
_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  0.0386
_diffrn_reflns_av_sigmaI/netI    0.0486
_diffrn_reflns_limit_h_max       44
_diffrn_reflns_limit_h_min       -44
_diffrn_reflns_limit_k_max       45
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -32
_diffrn_reflns_number            40700
_diffrn_reflns_theta_full        28.00
_diffrn_reflns_theta_max         28.00
_diffrn_reflns_theta_min         3.52
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.518
_exptl_absorpt_correction_T_max  0.940
_exptl_absorpt_correction_T_min  0.687
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS v.2.10 (Sheldrick, 2003)'
_exptl_crystal_colour            blue
_exptl_crystal_density_diffrn    1.350
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             10692
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.12
_platon_squeeze_details
;
The SQUEEZE procedure accounts for poorly resolved solvent molecules
lying in channels along the c axis. It is possible to model several
MeOH molecules using conventional refinement, but the best wR2 is
ca 25% and the su's on the bond distances and angles of the main
complexes are ca 2 times as large.

The total of ca 1500 electrons per unit cell amounts to
ca 84 MeOH molecule per cell, which corresponds to ca 4.5 per V complex.
;
_refine_diff_density_max         0.461
_refine_diff_density_min         -0.515
_refine_diff_density_rms         0.074
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.042
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     695
_refine_ls_number_reflns         13547
_refine_ls_number_restraints     30
_refine_ls_restrained_S_all      1.051
_refine_ls_R_factor_all          0.0664
_refine_ls_R_factor_gt           0.0505
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0770P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1264
_refine_ls_wR_factor_ref         0.1339
_reflns_number_gt                10499
_reflns_number_total             13547
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b918143c.txt
_cod_data_source_block           4
_cod_original_cell_volume        25539.7(15)
_cod_original_sg_symbol_H-M      'R -3'
_cod_database_code               7002819