Molecular Structures, Vibrational Spectroscopy, and Normal-Mode Analysis of M2(C\τbCR)4(PMe3)4 Dimetallatetraynes. Observation of Strongly Mixed Metal-Metal and Metal-Ligand Vibrational Modes
Kevin D. John; Vincent M. Miskowski; Michael A. Vance; Richard F. Dallinger; Louis C. Wang; Steven J. Geib; Michael D. Hopkins; Inorganic Chemistry 37 (1998) 6858–6873; doi:10.1021/ic980866u

data_4323259
_publ_section_title
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 Molecular Structures, Vibrational Spectroscopy, and Normal-Mode Analysis
 of M2(C\\tbCR)4(PMe3)4 Dimetallatetraynes. Observation of Strongly Mixed
 Metal-Metal and Metal-Ligand Vibrational Modes
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              6858
_journal_page_last               6873
_journal_paper_doi               10.1021/ic980866u
_journal_volume                  37
_journal_year                    1998
_chemical_formula_sum            'C36 H72 Mo2 P4'
_chemical_formula_weight         820.72
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_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                90.00
_cell_formula_units_Z            4
_cell_length_a                   13.498(3)
_cell_length_b                   18.056(5)
_cell_length_c                   19.805(4)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    208(2)
_cell_measurement_theta_max      12.5
_cell_measurement_theta_min      10
_cell_volume                     4827(2)
_computing_data_collection       'Siemens P3/PC'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      208(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Siemens P3'
_diffrn_measurement_method       'omega 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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0761
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            3254
_diffrn_reflns_theta_full        22.49
_diffrn_reflns_theta_max         22.5
_diffrn_reflns_theta_min         2
_diffrn_standards_decay_%        <1%
_diffrn_standards_interval_count 3
_diffrn_standards_interval_time  200
_exptl_absorpt_coefficient_mu    0.671
_exptl_absorpt_correction_type   psi-scan
_exptl_crystal_colour            'dark blue'
_exptl_crystal_density_diffrn    1.129
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1728
_exptl_crystal_size_max          0.47
_exptl_crystal_size_mid          0.42
_exptl_crystal_size_min          0.35
_refine_diff_density_max         0.449
_refine_diff_density_min         -0.332
_refine_diff_density_rms         0.085
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.0(3)
_refine_ls_extinction_coef       0.00001(17)
_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   0.967
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     249
_refine_ls_number_reflns         3254
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.967
_refine_ls_R_factor_all          0.1107
_refine_ls_R_factor_gt           0.0754
_refine_ls_shift/su_max          0.593
_refine_ls_shift/su_mean         0.037
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0969P)^2^+19.8758P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1756
_refine_ls_wR_factor_ref         0.1981
_reflns_number_gt                2372
_reflns_number_total             3254
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic980866u_2.cif
_cod_data_source_block           Mo2(CC-t-Bu)4(PMe3)4
_cod_depositor_comments
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The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'N/A' 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 
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_cod_database_code               4323259