W2Cl4(NR2)2(PR'3)2 Molecules. 8. Synthesis and Structural Characterization of Both Cis Isomers of Stoichiometry W2Cl4(NHR)2(PMe3)2, R = Et, Prn, and Bun. Direct Evidence Favoring an Internal Flip Mechanism for Cis-Trans Isomerization
F. Albert Cotton; Evgeny V. Dikarev; Wai-Yeung Wong; Inorganic Chemistry 36 (1997) 2670–2677; doi:10.1021/ic9700361

data_4323467
_publ_section_title
;
 W2Cl4(NR2)2(PR'3)2 Molecules. 8. Synthesis and Structural
 Characterization of Both Cis Isomers of Stoichiometry W2Cl4(NHR)2(PMe3)2,
 R = Et, Prn, and Bun. Direct Evidence Favoring an Internal Flip Mechanism
 for Cis-Trans Isomerization
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              2670
_journal_page_last               2677
_journal_paper_doi               10.1021/ic9700361
_journal_volume                  36
_journal_year                    1997
_chemical_compound_source        synthesized
_chemical_formula_analytical     'not measured'
_chemical_formula_moiety         'C10 H30 Cl4 N2 P2 W2'
_chemical_formula_structural     W2Cl4(NHEt)2(PMe3)2
_chemical_formula_sum            'C10 H30 Cl4 N2 P2 W2'
_chemical_formula_weight         749.80
_chemical_melting_point          ?
_chemical_name_common
;
 cis,cis-Tetrachloro-bis(ethylamido)-
 bis(trimethylphosphine) ditungsten(III)
;
_chemical_name_systematic
; 
 1,1,2,2-Tetrachloro-1,2-bis(ethylamido)-(cis,cis)-
 1,2-bis(trimethylphosphine)ditungsten(III) 
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL
_cell_angle_alpha                105.262(6)
_cell_angle_beta                 109.20(1)
_cell_angle_gamma                94.423(9)
_cell_formula_units_Z            1
_cell_length_a                   7.4366(2)
_cell_length_b                   8.8618(6)
_cell_length_c                   9.352(1)
_cell_measurement_reflns_used    250
_cell_measurement_temperature    213(2)
_cell_measurement_theta_max      41.6
_cell_measurement_theta_min      15.0
_cell_volume                     552.37(9)
_computing_cell_refinement       'MADNES (Enraf-Nonius, 1989)'
_computing_data_collection       'MADNES (Enraf-Nonius, 1989)'
_computing_data_reduction        'PROCOR (Kabsch, 1988)'
_computing_molecular_graphics    'SHELXTL V.5 (Siemens, 1994)'
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXTL V.5 (Siemens, 1994)'
_diffrn_ambient_temperature      213(2)
_diffrn_measurement_device       'Enraf-Nonius FAST'
_diffrn_measurement_method       '\w rotation 0.2\%'
_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    0.0240
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1831
_diffrn_reflns_theta_max         25.09
_diffrn_reflns_theta_min         2.42
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    11.026
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            red-brown
_exptl_crystal_density_diffrn    2.254
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    none
_exptl_crystal_description       needle-shaped
_exptl_crystal_F_000             350
_exptl_crystal_size_max          0.13
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.05
_refine_diff_density_max         1.776
_refine_diff_density_min         -1.000
_refine_diff_density_rms         0.207
_refine_ls_extinction_coef       noref
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.096
_refine_ls_goodness_of_fit_obs   1.085
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     95
_refine_ls_number_reflns         1828
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.152
_refine_ls_restrained_S_obs      1.085
_refine_ls_R_factor_all          0.0332
_refine_ls_R_factor_obs          0.0306
_refine_ls_shift/esd_max         0.001
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0392P)^2^+6.0327P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0838
_refine_ls_wR_factor_obs         0.0772
_reflns_number_observed          1752
_reflns_number_total             1831
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ic9700361_2.cif
_cod_data_source_block           W2Cl4(NHEt)2(PMe3)2
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value 'not measured' was changed to '?' -
the value is undefined or not given.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

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 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0392P)^2^+6.0327P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0392P)^2^+6.0327P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        552.37(7)
_cod_database_code               4323467