Organometallic single-molecule electronics: tuning electron transport through X(diphosphine)2FeC4Fe(diphosphine)2X building blocks by varying the Fe-X-Au anchoring scheme from coordinative to covalent.
Lissel, Franziska; Schwarz, Florian; Blacque, Olivier; Riel, Heike; Lörtscher, Emanuel; Venkatesan, Koushik; Berke, Heinz; Journal of the American Chemical Society 136 (2014) 14560–14569; doi:10.1021/ja507672g

data_4129263
_publ_section_title
;
 Organometallic single-molecule electronics: tuning electron transport
 through X(diphosphine)2FeC4Fe(diphosphine)2X building blocks by varying
 the Fe-X-Au anchoring scheme from coordinative to covalent.
;
_journal_issue                   41
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              14560
_journal_page_last               14569
_journal_paper_doi               10.1021/ja507672g
_journal_volume                  136
_journal_year                    2014
_chemical_formula_moiety         'C48 H102 Fe2 N2 P8, 3(C2 H3 N), 2(I)'
_chemical_formula_sum            'C54 H111 Fe2 I2 N5 P8'
_chemical_formula_weight         1443.73
_chemical_name_systematic
;Bis(acetonitrile)(\m^2^-buta-1,3-diyne-1,4-diyl)tetrakis[ethane-1,2-diylbis(diethylphosphane-\k<i>P</i>)]diiron(2+) diiodide acetonitrile solvate
(1:3)
;
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_atom_sites_solution_hydrogens   geom
_audit_creation_date             2013-11-20
_audit_creation_method
;
Olex2 1.2
(compiled 2013.11.15 svn.r2834 for OlexSys, GUI svn.r4709)
;
_cell_angle_alpha                94.204(1)
_cell_angle_beta                 101.929(1)
_cell_angle_gamma                92.428(1)
_cell_formula_units_Z            2
_cell_length_a                   10.3030(1)
_cell_length_b                   17.4632(2)
_cell_length_c                   20.3423(2)
_cell_measurement_reflns_used    38652
_cell_measurement_temperature    183(2)
_cell_measurement_theta_max      32.8
_cell_measurement_theta_min      2.6
_cell_volume                     3565.17(7)
_computing_cell_refinement
;
CrysAlisPro, Version 1.171.33.55 (Oxford Diffraction Ltd., 2010)
;
_computing_data_collection
;
CrysAlisPro, Version 1.171.33.55 (Oxford Diffraction Ltd., 2010)
;
_computing_data_reduction
;
CrysAlisPro, Version 1.171.33.55 (Oxford Diffraction Ltd., 2010)
;
_computing_molecular_graphics    'Mercury (Macrae et al., 2006)'
_computing_publication_material
;
Mercury (Macrae et al., 2006)
Olex2 (Dolomanov et al., 2009)
PLATON for Windows (Spek, 2003)
PublCIF (Westrip, 2010)
ShelXL2013 (Sheldrick, 2008) 
WinGX (Farrugia, 1999)
;
_computing_structure_refinement  'ShelXL2013 (Sheldrick, 2008)'
_computing_structure_solution    'ShelXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      183(2)
_diffrn_detector_area_resol_mean 10.4498
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Xcalibur, Ruby'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_UB_11      0.0075060000
_diffrn_orient_matrix_UB_12      0.0282137000
_diffrn_orient_matrix_UB_13      0.0276427000
_diffrn_orient_matrix_UB_21      -0.0234446000
_diffrn_orient_matrix_UB_22      0.0279669000
_diffrn_orient_matrix_UB_23      -0.0224819000
_diffrn_orient_matrix_UB_31      -0.0660482000
_diffrn_orient_matrix_UB_32      -0.0092876000
_diffrn_orient_matrix_UB_33      0.0030849000
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0218
_diffrn_reflns_av_unetI/netI     0.0214
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            63750
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.484
_diffrn_reflns_theta_min         2.562
_diffrn_source                   'Enhance (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    1.487
_exptl_absorpt_correction_T_max  0.761
_exptl_absorpt_correction_T_min  0.553
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
;
CrysAlisPro, Oxford Diffraction Ltd.,
Version 1.171.33.55 (release 05-01-2010 CrysAlis171 .NET)
(compiled Jan  5 2010,16:28:46)
Analytical numeric absorption correction using a multifaceted crystal
model based on expressions derived by R.C. Clark & J.S. Reid.
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897)
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.345
_exptl_crystal_description       tablet
_exptl_crystal_F_000             1496
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.38
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.985
_refine_diff_density_min         -0.381
_refine_diff_density_rms         0.055
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.065
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     703
_refine_ls_number_reflns         16349
_refine_ls_number_restraints     62
_refine_ls_restrained_S_all      1.073
_refine_ls_R_factor_all          0.0360
_refine_ls_R_factor_gt           0.0271
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0411P)^2^+0.3989P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0716
_refine_ls_wR_factor_ref         0.0736
_reflns_number_gt                13434
_reflns_number_total             16349
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja507672g_si_002.cif
_cod_data_source_block           2
_cod_database_code               4129263
_shelxl_version_number           2013-4
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H,H) groups, All C(H,H,H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Restrained distances
 C45A-C46A = C45B-C46B
 1.52 with sigma of 0.005
 C33-C34A = C33-C34B
 1.52 with sigma of 0.005
 P8-C46A = P8-C46B
 2.88 with sigma of 0.01
 C35-C36A \\sim C35-C36B
 with sigma of 0.005
 P8-C45A \\sim P8-C45B
 with sigma of 0.005
3. Uiso/Uaniso restraints and constraints
C45A \\sim C45B \\sim C46A \\sim C46B: within 3A with sigma of 0.005 and sigma
for terminal atoms of 0.01
C33 \\sim C34A \\sim C34B: within 2.5A with sigma of 0.005 and sigma for
terminal atoms of 0.01
4. Others
 Sof(H35A)=Sof(H35B)=Sof(C36B)=Sof(H36D)=Sof(H36E)=Sof(H36F)=1-FVAR(1)
 Sof(H35C)=Sof(H35D)=Sof(C36A)=Sof(H36A)=Sof(H36B)=Sof(H36C)=FVAR(1)
 Sof(C45B)=Sof(H45C)=Sof(H45D)=Sof(C46B)=Sof(H46D)=Sof(H46E)=Sof(H46F)=1-FVAR(2)
 Sof(C45A)=Sof(H45A)=Sof(H45B)=Sof(C46A)=Sof(H46A)=Sof(H46B)=Sof(H46C)=FVAR(2)
 Sof(H33C)=Sof(H33D)=Sof(C34B)=Sof(H34D)=Sof(H34E)=Sof(H34F)=1-FVAR(3)
 Sof(H33A)=Sof(H33B)=Sof(C34A)=Sof(H34A)=Sof(H34B)=Sof(H34C)=FVAR(3)
5.a Secondary CH2 refined with riding coordinates:
 C9(H9A,H9B), C10(H10A,H10B), C11(H11A,H11B), C13(H13A,H13B), C15(H15A,H15B),
 C17(H17A,H17B), C19(H19A,H19B), C20(H20A,H20B), C21(H21A,H21B), C23(H23A,H23B),
  C25(H25A,H25B), C27(H27A,H27B), C29(H29A,H29B), C30(H30A,H30B), C31(H31A,
 H31B), C33(H33A,H33B), C33(H33C,H33D), C35(H35C,H35D), C35(H35A,H35B),
 C37(H37A,H37B), C39(H39A,H39B), C40(H40A,H40B), C41(H41A,H41B), C43(H43A,H43B),
  C45A(H45A,H45B), C47(H47A,H47B), C45B(H45C,H45D)
5.b Idealised Me refined as rotating group:
 C6(H6A,H6B,H6C), C8(H8A,H8B,H8C), C12(H12A,H12B,H12C), C14(H14A,H14B,H14C),
 C16(H16A,H16B,H16C), C18(H18A,H18B,H18C), C22(H22A,H22B,H22C), C24(H24A,H24B,
 H24C), C26(H26A,H26B,H26C), C28(H28A,H28B,H28C), C32(H32A,H32B,H32C),
 C34A(H34A,H34B,H34C), C36A(H36A,H36B,H36C), C38(H38A,H38B,H38C), C42(H42A,H42B,
 H42C), C44(H44A,H44B,H44C), C48(H48A,H48B,H48C), C50(H50A,H50B,H50C), C52(H52A,
 H52B,H52C), C54(H54A,H54B,H54C), C36B(H36D,H36E,H36F), C46A(H46A,H46B,H46C),
 C46B(H46D,H46E,H46F), C34B(H34D,H34E,H34F)
;