A two-and-a-half-layer sandwich: potassium salt of anionic (η(4)-tetrasilacyclobutadiene)(η(5)-cyclopentadienyl)ruthenium.
Lee, Vladimir Ya; Takanashi, Kazunori; Sekiguchi, Akira; Dalton transactions (Cambridge, England : 2003) 39 (2010) 9229–9231; doi:10.1039/c0dt00009d

data_7025813
_publ_section_title
;
 A two-and-a-half-layer sandwich: potassium salt of anionic
 (\h(4)-tetrasilacyclobutadiene)(\h(5)-cyclopentadienyl)ruthenium.
;
_journal_issue                   39
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              9229
_journal_page_last               9231
_journal_paper_doi               10.1039/c0dt00009d
_journal_volume                  39
_journal_year                    2010
_chemical_formula_sum            'C54 H115 K O2 Ru Si8'
_chemical_formula_weight         1161.35
_chemical_name_common            (tBu2MeSi)4Si4RuCpK
_chemical_name_systematic
;
(tBu2MeSi)4Si4RuCpK
;
_space_group_IT_number           56
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ab 2ac'
_symmetry_space_group_name_H-M   'P c c n'
_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            8
_cell_length_a                   20.5640(5)
_cell_length_b                   44.9360(4)
_cell_length_c                   14.2880(13)
_cell_measurement_reflns_used    122209
_cell_measurement_temperature    150.0(1)
_cell_measurement_theta_max      27.92
_cell_measurement_theta_min      2.20
_cell_volume                     13203.0(12)
_computing_cell_refinement       'HKL scalepack'
_computing_data_collection       'MacScience Xpress'
_computing_data_reduction        Denzo
_computing_molecular_graphics    ORTEP
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    SIR92
_diffrn_ambient_temperature      150.0(1)
_diffrn_measured_fraction_theta_full 0.941
_diffrn_measured_fraction_theta_max 0.941
_diffrn_measurement_device       'MacScience DIP2030 Image plate'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0795
_diffrn_reflns_limit_h_max       27
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       59
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            14892
_diffrn_reflns_theta_full        27.92
_diffrn_reflns_theta_max         27.92
_diffrn_reflns_theta_min         2.20
_exptl_absorpt_coefficient_mu    0.480
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.169
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       cube
_exptl_crystal_F_000             5040
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.2
_refine_diff_density_max         1.281
_refine_diff_density_min         -1.019
_refine_diff_density_rms         0.109
_refine_ls_extinction_coef       0.00138(10)
_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   1.019
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     596
_refine_ls_number_reflns         14892
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.019
_refine_ls_R_factor_all          0.1088
_refine_ls_R_factor_gt           0.0639
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0872P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1470
_refine_ls_wR_factor_ref         0.1697
_reflns_number_gt                9512
_reflns_number_total             14892
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c0dt00009d.txt
_cod_data_source_block           shelxl
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 
;
_cod_original_sg_symbol_H-M      'P c c n '
_cod_database_code               7025813