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_1576116
_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         'C56 H48 B4 Zr, C7 H8'
_chemical_formula_sum            'C63 H56 B4 Zr'
_chemical_formula_weight         947.53
_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             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                111.2930(10)
_cell_angle_beta                 91.3460(10)
_cell_angle_gamma                107.0270(10)
_cell_formula_units_Z            2
_cell_length_a                   11.4439(5)
_cell_length_b                   14.8148(6)
_cell_length_c                   16.3854(5)
_cell_measurement_reflns_used    9922
_cell_measurement_temperature    100.00
_cell_measurement_theta_max      27.896
_cell_measurement_theta_min      2.425
_cell_volume                     2448.46(17)
_computing_cell_refinement       'SAINT V8.40B (?, 2016)'
_computing_data_reduction        'SAINT V8.40B (?, 2016)'
_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 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker D8 VENTURE DUO'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0786
_diffrn_reflns_av_unetI/netI     0.0401
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            88255
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.102
_diffrn_reflns_theta_min         2.018
_exptl_absorpt_coefficient_mu    0.266
_exptl_absorpt_correction_T_max  0.7457
_exptl_absorpt_correction_T_min  0.7260
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1031 before and 0.0527 after correction.
The Ratio of minimum to maximum transmission is 0.9736.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear greenish yellow'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   greenish
_exptl_crystal_colour_primary    yellow
_exptl_crystal_density_diffrn    1.285
_exptl_crystal_description       block
_exptl_crystal_F_000             988
_exptl_crystal_preparation       'Salt metathesis'
_exptl_crystal_recrystallization_method
'Concentrated toluene solution vapor diffused with pentane'
_exptl_crystal_size_max          0.22
_exptl_crystal_size_mid          0.116
_exptl_crystal_size_min          0.093
_refine_diff_density_max         0.393
_refine_diff_density_min         -0.712
_refine_diff_density_rms         0.061
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.043
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     683
_refine_ls_number_reflns         10792
_refine_ls_number_restraints     261
_refine_ls_restrained_S_all      1.032
_refine_ls_R_factor_all          0.0548
_refine_ls_R_factor_gt           0.0395
_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^)+(0.0398P)^2^+1.9062P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0906
_refine_ls_wR_factor_ref         0.0985
_reflns_Friedel_coverage         0.000
_reflns_number_gt                8885
_reflns_number_total             10792
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5sc06254c3.cif
_cod_data_source_block           mo_dal24_07
_cod_depositor_comments
'Adding full bibliography for 1576111--1576117.cif.'
_cod_original_cell_volume        2448.45(17)
_cod_database_code               1576116
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   0.976
_shelx_estimated_absorpt_t_min   0.944
_olex2_refinement_description
;
1. 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
2. Restrained distances
 C57-C58 \\sim C57A-C58A
 with sigma of 0.02
 C58-C59 \\sim C58A-C59A
 with sigma of 0.02
 C58-C63 \\sim C58A-C63A
 with sigma of 0.02
 C59-C60 \\sim C59A-C60A
 with sigma of 0.02
 C60-C61 \\sim C60A-C61A
 with sigma of 0.02
 C61-C62 \\sim C61A-C62A
 with sigma of 0.02
 C62-C63 \\sim C62A-C63A
 with sigma of 0.02
 C57-C59 \\sim C57A-C59A
 with sigma of 0.04
 C57-C63 \\sim C57A-C63A
 with sigma of 0.04
 C58-C60 \\sim C58A-C60A
 with sigma of 0.04
 C58-C62 \\sim C58A-C62A
 with sigma of 0.04
 C59-C61 \\sim C59A-C61A
 with sigma of 0.04
 C59-C63 \\sim C59A-C63A
 with sigma of 0.04
 C60-C62 \\sim C60A-C62A
 with sigma of 0.04
 C61-C63 \\sim C61A-C63A
 with sigma of 0.04
3. Uiso/Uaniso restraints and constraints
C57 \\sim C58 \\sim C59 \\sim C60 \\sim C61 \\sim C62 \\sim C63 \\sim C57A
\\sim C58A \\sim C63A \\sim C62A \\sim C61A \\sim C60A \\sim C59A: within 2A
with sigma of 0.01 and sigma for terminal atoms of 0.02 within 2A
4. Rigid body (RIGU) restrains
 C57, C58, C59, C60, C61, C62, C63, C57A, C58A, C63A, C62A, C61A, C60A, C59A
 with sigma for 1-2 distances of 0.001 and sigma for 1-3 distances of 0.001
5. Others
 Sof(C57A)=Sof(H57D)=Sof(H57E)=Sof(H57F)=Sof(C58A)=Sof(C63A)=Sof(H63A)=
 Sof(C62A)=Sof(H62A)=Sof(C61A)=Sof(H61A)=Sof(C60A)=Sof(H60A)=Sof(C59A)=
 Sof(H59A)=1-FVAR(1)
 Sof(C57)=Sof(H57A)=Sof(H57B)=Sof(H57C)=Sof(C58)=Sof(C59)=Sof(H59)=Sof(C60)=
 Sof(H60)=Sof(C61)=Sof(H61)=Sof(C62)=Sof(H62)=Sof(C63)=Sof(H63)=FVAR(1)
6.a Aromatic/amide H refined with riding coordinates:
 C3(H3), C4(H4), C5(H5), C6(H6), C8(H8), C10(H10), C11(H11), C12(H12),
 C13(H13), C17(H17), C18(H18), C19(H19), C20(H20), C22(H22), C24(H24), C25(H25),
  C26(H26), C27(H27), C31(H31), C32(H32), C33(H33), C34(H34), C36(H36),
 C38(H38), C39(H39), C40(H40), C41(H41), C45(H45), C46(H46), C47(H47), C48(H48),
  C50(H50), C52(H52), C53(H53), C54(H54), C55(H55), C59(H59), C60(H60),
 C61(H61), C62(H62), C63(H63), C63A(H63A), C62A(H62A), C61A(H61A), C60A(H60A),
 C59A(H59A)
6.b Idealised Me refined as rotating group:
 B1(H1A,H1B,H1C), B2(H2A,H2B,H2C), B3(H3A,H3B,H3C), B4(H4A,H4B,H4C), C57(H57A,
 H57B,H57C), C57A(H57D,H57E,H57F)
;
_shelx_res_checksum              81043
_olex2_submission_special_instructions 'No special instructions were received'