The behavior of potassium follows that of calcium in heterobimetallic 'K-H-Al' hydrides on a picolyl-derived chemically non-innocent triaza ligand.
Mandal, Chhotan; Kundu, Abhishek; Panda, Sourav; Mukherjee, Debabrata; Dalton transactions (Cambridge, England : 2003) 55 (2026) 3934–3942; doi:10.1039/d6dt00079g

data_7720147
_publ_section_title
;
 The behavior of potassium follows that of calcium in heterobimetallic
 'K-H-Al' hydrides on a picolyl-derived chemically non-innocent triaza
 ligand.
;
_journal_issue                   9
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              3934
_journal_page_last               3942
_journal_paper_doi               10.1039/d6dt00079g
_journal_volume                  55
_journal_year                    2026
_chemical_formula_moiety
'C108 H192 Al4 K4 N16 Si8, 2(C6 H14), 1.6[C6H14]'
_chemical_formula_sum            'C120 H220 Al4 K4 N16 Si8'
_chemical_formula_weight         2376.15
_space_group_crystal_system      tetragonal
_space_group_IT_number           82
_space_group_name_Hall           'I -4'
_space_group_name_H-M_alt        'I -4'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     iterative
_audit_creation_date             2025-08-18
_audit_creation_method
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_audit_update_record
;
2025-08-21 deposited with the CCDC.	2026-02-03 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   19.0760(10)
_cell_length_b                   19.0760(10)
_cell_length_c                   20.9168(13)
_cell_measurement_reflns_used    6597
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.029
_cell_measurement_theta_min      2.578
_cell_volume                     7611.5(7)
_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    'olex2.solve 1.5 (Bourhis et al., 2015)'
_diffrn_ambient_temperature      100.00
_diffrn_measured_fraction_theta_full 0.981
_diffrn_measured_fraction_theta_max 0.981
_diffrn_measurement_device_type  'Bruker SMART CCD 6000 area detector'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1757
_diffrn_reflns_av_unetI/netI     0.0810
_diffrn_reflns_Laue_measured_fraction_full 0.981
_diffrn_reflns_Laue_measured_fraction_max 0.981
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            77619
_diffrn_reflns_point_group_measured_fraction_full 0.980
_diffrn_reflns_point_group_measured_fraction_max 0.980
_diffrn_reflns_theta_full        25.029
_diffrn_reflns_theta_max         25.029
_diffrn_reflns_theta_min         2.578
_exptl_absorpt_coefficient_mu    0.248
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.616
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            'clear bluish blue'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   bluish
_exptl_crystal_colour_primary    blue
_exptl_crystal_density_diffrn    1.037
_exptl_crystal_description       block
_exptl_crystal_F_000             2584
_exptl_crystal_preparation       'solvent diffusion'
_exptl_crystal_size_max          0.0128
_exptl_crystal_size_mid          0.0125
_exptl_crystal_size_min          0.001
_refine_diff_density_max         0.272
_refine_diff_density_min         -0.268
_refine_diff_density_rms         0.055
_refine_ls_abs_structure_details
;
 Flack x determined using 1988 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.02(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.991
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     347
_refine_ls_number_reflns         6597
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.992
_refine_ls_R_factor_all          0.0829
_refine_ls_R_factor_gt           0.0522
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0800P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1239
_refine_ls_wR_factor_ref         0.1408
_reflns_Friedel_coverage         0.936
_reflns_Friedel_fraction_full    0.979
_reflns_Friedel_fraction_max     0.979
_reflns_number_gt                4895
_reflns_number_total             6597
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6dt00079g2.cif
_cod_data_source_block           cm15
_cod_depositor_comments
'Adding full bibliography for 7720145--7720151.cif.'
_cod_original_cell_volume        7611.5(9)
_cod_database_code               7720147
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   1.000
_shelx_estimated_absorpt_t_min   0.997
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Restrained distances
 C30-C29 \\sim C29-C28
 with sigma of 0.02
3. Uiso/Uaniso restraints and constraints
Uanis(C30) = Uanis(C29) = Uanis(C28)
4.a Secondary CH2 refined with riding coordinates:
 C16(H16A,H16B), C17(H17A,H17B), C18(H18A,H18B), C20(H20A,H20B), C30(H30A,
 H30B), C29(H29A,H29B)
4.b Aromatic/amide H refined with riding coordinates:
 C12(H12), C2(H2), C9(H9), C3(H3), C15(H15), C4(H4)
4.c Idealised Me refined as rotating group:
 C23(H23A,H23B,H23C), C11(H11A,H11B,H11C), C8(H8C,H8A,H8B), C22(H22A,H22B,
 H22C), C14(H14A,H14B,H14C), C25(H25A,H25B,H25C), C26(H26A,H26B,H26C), C19(H19A,
 H19B,H19C), C24(H24A,H24B,H24C), C27(H27A,H27B,H27C), C21(H21A,H21B,H21C),
 C28(H28A,H28B,H28C)
;
_smtbx_masks_special_details
;
A solvent mask was calculated and 184 electrons were 
found in a volume of 916\%A^3^ in 3 voids per unit cell. 
This is consistent with the presence of 
0.4[C6H14] per formula unit 
which account for 160 electrons 
per unit cell.
;
_shelx_res_checksum              31088
_shelx_fab_checksum              20814
_olex2_submission_special_instructions 'No special instructions were received'