Direct measurement of covalent three-center, two-electron M-H-B bonding in Zr and Hf borohydrides using B K-edge XAS.
Hansen, Hannah M.; Zgrabik, Joshua C.; Zacher, 3rd, Peter A; Schuely, Jacob J.; Amano, Emily M.; Yang, Mai Yer; Unruh, Daniel K.; Zuin, Lucia; Keith, Jason M.; Daly, Scott R.; Chemical science 16 (2025) 22333–22347; doi:10.1039/d5sc06254c

data_1576117
_publ_section_title
;
 Direct measurement of covalent three-center, two-electron M-H-B bonding
 in Zr and Hf borohydrides using B K-edge XAS.
;
_journal_issue                   47
_journal_name_full               'Chemical science'
_journal_page_first              22333
_journal_page_last               22347
_journal_paper_doi               10.1039/d5sc06254c
_journal_volume                  16
_journal_year                    2025
_chemical_formula_moiety         'C60 H104 B4 Hf'
_chemical_formula_sum            'C60 H104 B4 Hf'
_chemical_formula_weight         1047.16
_space_group_crystal_system      monoclinic
_space_group_IT_number           9
_space_group_name_Hall           'C -2yc'
_space_group_name_H-M_alt        'C 1 c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_date             2025-06-10
_audit_creation_method
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_audit_update_record
;
2025-06-12 deposited with the CCDC.	2025-10-13 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 121.9750(10)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   27.2122(13)
_cell_length_b                   20.4002(11)
_cell_length_c                   25.5853(16)
_cell_measurement_reflns_used    8052
_cell_measurement_temperature    100.00
_cell_measurement_theta_max      26.253
_cell_measurement_theta_min      3.223
_cell_volume                     12048.3(12)
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_temperature      100.00
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker D8 VENTURE DUO'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0570
_diffrn_reflns_av_unetI/netI     0.0386
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       38
_diffrn_reflns_limit_h_min       -38
_diffrn_reflns_limit_k_max       29
_diffrn_reflns_limit_k_min       -29
_diffrn_reflns_limit_l_max       35
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            218411
_diffrn_reflns_point_group_measured_fraction_full 0.969
_diffrn_reflns_point_group_measured_fraction_max 0.913
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.563
_diffrn_reflns_theta_min         1.879
_exptl_absorpt_coefficient_mu    1.765
_exptl_crystal_colour            'clear whiteish colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   whiteish
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.155
_exptl_crystal_description       block
_exptl_crystal_F_000             4448
_exptl_crystal_size_max          0.293
_exptl_crystal_size_mid          0.133
_exptl_crystal_size_min          0.117
_refine_diff_density_max         0.963
_refine_diff_density_min         -1.026
_refine_diff_density_rms         0.082
_refine_ls_abs_structure_details
;
 Refined as an inversion twin.
;
_refine_ls_abs_structure_Flack   0.484(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.031
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1318
_refine_ls_number_reflns         33770
_refine_ls_number_restraints     327
_refine_ls_restrained_S_all      1.034
_refine_ls_R_factor_all          0.0331
_refine_ls_R_factor_gt           0.0298
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0185P)^2^+26.1000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0604
_refine_ls_wR_factor_ref         0.0617
_reflns_Friedel_coverage         0.840
_reflns_Friedel_fraction_full    0.939
_reflns_Friedel_fraction_max     0.834
_reflns_number_gt                32215
_reflns_number_total             33770
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5sc06254c3.cif
_cod_data_source_block           mo_dal23_37
_cod_depositor_comments
'Adding full bibliography for 1576111--1576117.cif.'
_cod_database_code               1576117
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   0.820
_shelx_estimated_absorpt_t_min   0.626
_olex2_refinement_description
;
1. Twinned data refinement
 Scales: 0.516(5)
 0.484(5)
2. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All B(H,H,H) groups, All C(H,H,H) groups
3. Restrained distances
 H7B-H97 = H8D-H112 = H8F-H115
 2.1 with sigma of 0.02
 C4-C13 \\sim C4-C13A
 with sigma of 0.02
 C13-C14 \\sim C13A-C14A
 with sigma of 0.02
 C13-C15 \\sim C13A-C15A
 with sigma of 0.02
 C4-C14 \\sim C4-C14A
 with sigma of 0.04
 C4-C15 \\sim C4-C15A
 with sigma of 0.04
 C14-C15 \\sim C14A-C15A
 with sigma of 0.04
 C19-C28 \\sim C19-C28A
 with sigma of 0.02
 C30-C28 \\sim C30A-C28A
 with sigma of 0.02
 C28-C29 \\sim C28A-C29A
 with sigma of 0.02
 C19-C30 \\sim C19-C30A
 with sigma of 0.04
 C19-C29 \\sim C19-C29A
 with sigma of 0.04
 C30-C29 \\sim C30A-C29A
 with sigma of 0.04
 C34-C43 \\sim C34-C43A
 with sigma of 0.02
 C43-C44 \\sim C43A-C44A
 with sigma of 0.02
 C43-C45 \\sim C43A-C45A
 with sigma of 0.02
 C34-C44 \\sim C34-C44A
 with sigma of 0.04
 C34-C45 \\sim C34-C45A
 with sigma of 0.04
 C44-C45 \\sim C44A-C45A
 with sigma of 0.04
4. Uiso/Uaniso restraints and constraints
C13 \\sim C14 \\sim C15 \\sim C13A \\sim C14A \\sim C15A: within 2A with sigma
of 0.01 and sigma for terminal atoms of 0.02 within 2A
C28 \\sim C29 \\sim C30 \\sim C28A \\sim C29A \\sim C30A: within 2A with sigma
of 0.01 and sigma for terminal atoms of 0.02 within 2A
C34 \\sim C43 \\sim C44 \\sim C45 \\sim C43A \\sim C44A \\sim C45A: within 2A
with sigma of 0.01 and sigma for terminal atoms of 0.02 within 2A
5. Rigid body (RIGU) restrains
 C13, C14, C15, C13A, C14A, C15A
 with sigma for 1-2 distances of 0.001 and sigma for 1-3 distances of 0.001
 C28, C29, C30, C28A, C29A, C30A
 with sigma for 1-2 distances of 0.001 and sigma for 1-3 distances of 0.001
 C34, C43, C44, C45, C43A, C44A, C45A
 with sigma for 1-2 distances of 0.001 and sigma for 1-3 distances of 0.001
6. Others
 Sof(C13A)=Sof(H13A)=Sof(C14A)=Sof(H14D)=Sof(H14E)=Sof(H14F)=Sof(C15A)=
 Sof(H15D)=Sof(H15E)=Sof(H15F)=1-FVAR(1)
 Sof(C13)=Sof(H13)=Sof(C14)=Sof(H14A)=Sof(H14B)=Sof(H14C)=Sof(C15)=Sof(H15A)=
 Sof(H15B)=Sof(H15C)=FVAR(1)
 Sof(C28A)=Sof(H28A)=Sof(C29A)=Sof(H29D)=Sof(H29E)=Sof(H29F)=Sof(C30A)=
 Sof(H30D)=Sof(H30E)=Sof(H30F)=1-FVAR(2)
 Sof(C28)=Sof(H28)=Sof(C29)=Sof(H29A)=Sof(H29B)=Sof(H29C)=Sof(C30)=Sof(H30A)=
 Sof(H30B)=Sof(H30C)=FVAR(2)
 Sof(C43A)=Sof(H43A)=Sof(C44A)=Sof(H44D)=Sof(H44E)=Sof(H44F)=Sof(C45A)=
 Sof(H45D)=Sof(H45E)=Sof(H45F)=1-FVAR(3)
 Sof(C43)=Sof(H43)=Sof(C44)=Sof(H44A)=Sof(H44B)=Sof(H44C)=Sof(C45)=Sof(H45A)=
 Sof(H45B)=Sof(H45C)=FVAR(3)
7.a Ternary CH refined with riding coordinates:
 C7(H7), C10(H10), C22(H22), C25(H25), C37(H37), C40(H40), C52(H52), C55(H55),
 C58(H58), C13(H13), C28(H28), C43(H43), C13A(H13A), C28A(H28A), C43A(H43A),
 C67(H67), C70(H70), C73(H73), C82(H82), C85(H85), C88(H88), C97(H97),
 C100(H100), C103(H103), C112(H112), C115(H115), C118(H118)
7.b Aromatic/amide H refined with riding coordinates:
 C3(H3), C5(H5), C18(H18), C20(H20), C33(H33), C35(H35), C48(H48), C50(H50),
 C63(H63), C65(H65), C78(H78), C80(H80), C93(H93), C95(H95), C108(H108),
 C110(H110)
7.c Idealised Me refined as rotating group:
 C8(H8A,H8B,H8C), C9(H9A,H9B,H9C), C11(H11A,H11B,H11C), C12(H12A,H12B,H12C),
 C23(H23A,H23B,H23C), C24(H24A,H24B,H24C), C26(H26A,H26B,H26C), C27(H27A,H27B,
 H27C), C38(H38A,H38B,H38C), C39(H39A,H39B,H39C), C41(H41A,H41B,H41C), C42(H42A,
 H42B,H42C), C53(H53A,H53B,H53C), C54(H54A,H54B,H54C), C56(H56A,H56B,H56C),
 C57(H57A,H57B,H57C), C59(H59A,H59B,H59C), C60(H60A,H60B,H60C), B1(H1A,H1B,H1C),
  B2(H2A,H2B,H2C), B3(H3A,H3B,H3C), B4(H4A,H4B,H4C), C14(H14A,H14B,H14C),
 C15(H15A,H15B,H15C), C29(H29A,H29B,H29C), C30(H30A,H30B,H30C), C44(H44A,H44B,
 H44C), C45(H45A,H45B,H45C), C14A(H14D,H14E,H14F), C15A(H15D,H15E,H15F),
 C29A(H29D,H29E,H29F), C30A(H30D,H30E,H30F), C44A(H44D,H44E,H44F), C45A(H45D,
 H45E,H45F), C68(H68A,H68B,H68C), C69(H69A,H69B,H69C), C71(H71A,H71B,H71C),
 C72(H72A,H72B,H72C), C74(H74A,H74B,H74C), C75(H75A,H75B,H75C), C83(H83A,H83B,
 H83C), C84(H84A,H84B,H84C), C86(H86A,H86B,H86C), C87(H87A,H87B,H87C), C89(H89A,
 H89B,H89C), C90(H90A,H90B,H90C), C98(H98A,H98B,H98C), C99(H99A,H99B,H99C),
 C101(H10A,H10B,H10C), C102(H10D,H10E,H10F), C104(H10G,H10H,H10I), C105(H10J,
 H10K,H10L), C113(H11D,H11E,H11F), C114(H11G,H11H,H11I), C116(H11J,H11K,H11L),
 C117(H11M,H11N,H11O), C119(H11P,H11Q,H11R), C120(H12D,H12E,H12F), B5(H5A,H5B,
 H5C), B6(H6A,H6B,H6C), B7(H7A,H7B,H7C), B8(H8D,H8E,H8F)
;
_shelx_res_checksum              13792
_olex2_submission_special_instructions 'No special instructions were received'