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#$Date: 2025-08-19 00:52:38 +0200 (Tue 19 de Aug de 2025) $
#$Revision: 301791 $
#$URL: svn://www.crystallography.net/cod/cif/2/00/19/2001979.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/. The original data for this entry
# were provided by IUCr Journals, http://journals.iucr.org/.
#
# The file may be used within the scientific community so long as
# proper attribution is given to the journal article from which the
# data were obtained.
#
data_2001979
loop_
_publ_author_name
'Fronczek, F. R.'
'Lickiss, P. D.'
_publ_section_title
;
 Structure of the highly crowded alkyne
 di[tris(trimethylsilyl)methyl]acetylene and the octasilane
 hexakis(trimethylsilyl)disilane
;
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              331
_journal_page_last               333
_journal_paper_doi               10.1107/S0108270192002737
_journal_volume                  49
_journal_year                    1993
_chemical_formula_sum            'C18 H54 Si8'
_chemical_formula_weight         495.3
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3 2"c'
_symmetry_space_group_name_H-M   'R -3 c'
_cell_angle_alpha                90.0000
_cell_angle_beta                 90.0000
_cell_angle_gamma                120.0000
_cell_formula_units_Z            6
_cell_length_a                   16.154(2)
_cell_length_b                   16.154(2)
_cell_length_c                   22.859(3)
_cell_volume                     5165.9(11)
_diffrn_radiation_type           Cu
_diffrn_radiation_wavelength     1.54184
_exptl_absorpt_coefficient_mu    3.011
_exptl_crystal_density_diffrn    0.955
_exptl_crystal_F_000             1644
_cod_data_source_file            he0040.cif
_cod_data_source_block           he0040_structure_2_of_2
_cod_original_cell_volume        5166.1(13)
_cod_original_sg_symbol_H-M      'R -3 c {hexagonal axes}'
_cod_database_code               2001979
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Si1 .0 .0 .19744(5)
Si2 .05750(5) .15396(5) .15601(3)
C1 .0882(3) .1553(3) .07670(10)
C2 -.0333(2) .1922(2) .1592(2)
C3 .1678(2) .2508(2) .1904(2)
H1A .1347 .1361 .0729
H1B .0323 .1124 .0556
H1C .1131 .2180 .0615
H2A -.0911 .1444 .1420
H2B -.0445 .2012 .1988
H2C -.0106 .2505 .1384
H3A .1570 .2539 .2309
H3B .2186 .2378 .1853
H3C .1842 .3101 .1724
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
Si2 C1 1.876(3)
Si2 C3 1.858(3)
Si1 Si2 2.3738(9)
Si2 C2 1.855(4)
loop_
_cod_related_entry_id
_cod_related_entry_database
_cod_related_entry_code
1 PubChem 3434155
