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_7720145
_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         'C48 H84 Al2 K2 N8 Si4, 1.3[C7H8]'
_chemical_formula_sum            'C57.1 H94.4 Al2 K2 N8 Si4'
_chemical_formula_weight         1137.52
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_date             2025-08-20
_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                 107.328(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   16.3277(11)
_cell_length_b                   17.4691(10)
_cell_length_c                   25.4513(18)
_cell_measurement_reflns_used    6331
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.350
_cell_measurement_theta_min      2.103
_cell_volume                     6930.0(8)
_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 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_temperature      100.00
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device       'three-circle diffractometer'
_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  0.0697
_diffrn_reflns_av_unetI/netI     0.0216
_diffrn_reflns_Laue_measured_fraction_full 0.995
_diffrn_reflns_Laue_measured_fraction_max 0.995
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            146411
_diffrn_reflns_point_group_measured_fraction_full 0.995
_diffrn_reflns_point_group_measured_fraction_max 0.995
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.350
_diffrn_reflns_theta_min         2.103
_exptl_absorpt_coefficient_mu    0.270
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.614
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            'clear greenish green'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   greenish
_exptl_crystal_colour_primary    green
_exptl_crystal_density_diffrn    1.090
_exptl_crystal_description       block
_exptl_crystal_F_000             2452
_exptl_crystal_size_max          0.0128
_exptl_crystal_size_mid          0.0123
_exptl_crystal_size_min          0.0111
_refine_diff_density_max         1.224
_refine_diff_density_min         -0.341
_refine_diff_density_rms         0.059
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.055
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     301
_refine_ls_number_reflns         6331
_refine_ls_number_restraints     36
_refine_ls_restrained_S_all      1.055
_refine_ls_R_factor_all          0.0488
_refine_ls_R_factor_gt           0.0413
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0715P)^2^+8.4305P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1191
_refine_ls_wR_factor_ref         0.1267
_reflns_Friedel_coverage         0.000
_reflns_number_gt                5355
_reflns_number_total             6331
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6dt00079g2.cif
_cod_data_source_block           dmcmal10_0m
_cod_depositor_comments
'Adding full bibliography for 7720145--7720151.cif.'
_cod_original_formula_sum        'C57.10 H94.40 Al2 K2 N8 Si4'
_cod_database_code               7720145
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   0.997
_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. Rigid body (RIGU) restrains
 C2, C3, C4, C5, N1, C1
 with sigma for 1-2 distances of 0.001 and sigma for 1-3 distances of 0.001
3.a Ternary CH refined with riding coordinates:
 C12(H12)
3.b Secondary CH2 refined with riding coordinates:
 C13(H13A,H13B), C14(H14A,H14B), C17(H17A,H17B), C15(H15A,H15B)
3.c Aromatic/amide H refined with riding coordinates:
 C2(H2), C7(H7), C4(H4), C11(H11), C10(H10), C8(H8), C3(H3), C9(H9)
3.d Idealised Me refined as rotating group:
 C22(H22A,H22B,H22C), C23(H23A,H23B,H23C), C24(H24A,H24B,H24C), C21(H21A,H21B,
 H21C), C19(H19A,H19B,H19C), C20(H20A,H20B,H20C), C16(H16A,H16B,H16C), C18(H18A,
 H18B,H18C)
;
_smtbx_masks_special_details
;
A solvent mask was calculated and 250 electrons were 
found in a volume of 1796\%A^3^ in 1 void per unit cell. 
This is consistent with the presence of 
0.65[C7H8] per Formula Unit 
which account for 260 electrons 
per unit cell.
;
_shelx_res_checksum              63806
_shelx_fab_checksum              69915
_olex2_submission_special_instructions 'No special instructions were received'