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_7720151
_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 H88 Al2 K2 N8 Si4'
_chemical_formula_sum            'C48 H88 Al2 K2 N8 Si4'
_chemical_formula_weight         1021.78
_space_group_crystal_system      tetragonal
_space_group_IT_number           86
_space_group_name_Hall           '-P 4bc'
_space_group_name_H-M_alt        'P 42/n :2'
_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            8
_cell_length_a                   28.85990(10)
_cell_length_b                   28.85990(10)
_cell_length_c                   14.50340(10)
_cell_measurement_reflns_used    51487
_cell_measurement_temperature    100.03(19)
_cell_measurement_theta_max      67.8130
_cell_measurement_theta_min      2.1590
_cell_volume                     12079.79(10)
_computing_cell_refinement       'CrysAlisPro 1.171.41.105a (Rigaku OD, 2021)'
_computing_data_collection       'CrysAlisPro 1.171.41.105a (Rigaku OD, 2021)'
_computing_data_reduction        'CrysAlisPro 1.171.41.105a (Rigaku OD, 2021)'
_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      100.15
_diffrn_detector_area_resol_mean 10.0000
_diffrn_detector_type            HyPix3000
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w   -108.00 -27.00   0.50    5.73    --  -40.58 -32.00-164.00  162
  2  \w   -109.00 -52.00   0.50    5.73    --  -40.58-155.00-178.00  114
  3  \w   -107.00 -27.00   0.50    5.73    --  -40.58 155.00-140.00  160
  4  \w    -37.00  27.00   0.50    5.73    --  -40.58  32.00  -5.00  128
  5  \w    -73.00  31.00   0.50    5.73    --  -40.58  92.00 169.00  208
  6  \w    -27.00  37.00   0.50    5.73    --   40.58 -32.00-164.00  128
  7  \w     30.00  86.00   0.50    5.73    --   40.58-120.00 -21.00  112
  8  \w    -80.00 -11.00   0.50   22.93    --  -82.50  92.00 169.00  138
  9  \w   -107.00 -27.00   0.50   22.93    --  -82.50 155.00-140.00  160
 10  \w   -150.00 -69.00   0.50   22.93    --  -82.50 -32.00-164.00  162
 11  \w     32.00 110.00   0.50   22.93    --   96.35-120.00 -21.00  156
 12  \w    101.00 168.00   0.50   22.93    --   96.35  92.00 169.00  134
 13  \w     74.00 162.00   0.50   22.93    --   96.35 155.00-140.00  176
 14  \w     49.00 133.00   0.50   22.93    --   96.35-155.00-178.00  168
 15  \w     25.00 106.00   0.50   22.93    --   96.35 -92.00  57.00  162
 16  \w     83.00 164.00   0.50   22.93    --   96.35  32.00  -5.00  162
 17  \w    -43.00  26.00   0.50    5.73    --  -40.58  38.00-150.00  138
 18  \w   -111.00 -26.00   0.50    5.73    --  -40.58 -25.00   0.00  170
 19  \w     28.00 109.00   0.50    5.73    --   40.58  32.00  -5.00  162
 20  \w    -47.00 -15.00   0.50   22.93    --  -82.50  42.00-150.00   64
 21  \w    -85.00 -18.00   0.50   22.93    --  -82.50 120.00  62.00  134
 22  \w     30.00  57.00   0.50   22.93    --   96.35 -50.00  60.00   54
 23  \w     29.00  83.00   0.50   22.93    --   96.35 -68.00 -60.00  108
 24  \w     30.00  57.00   0.50   22.93    --   96.35 -50.00 -60.00   54
 25  \w     33.00 110.00   0.50   22.93    --   96.35-117.00  60.00  154
 26  \w     30.00  57.00   0.50   22.93    --   96.35 -50.00  30.00   54
 27  \w     28.00  68.00   0.50   22.93    --   96.35 -59.00 -30.00   80
 28  \w     28.00  68.00   0.50   22.93    --   96.35 -59.00-120.00   80
 29  \w     28.00  68.00   0.50   22.93    --   96.35 -59.00  30.00   80
 30  \w     30.00  57.00   0.50   22.93    --   96.35 -50.00 -30.00   54
 31  \w   -109.00 -14.00   0.50    5.73    --  -40.58 -77.00-180.00  190
 32  \w   -109.00 -14.00   0.50    5.73    --  -40.58 -77.00 -30.00  190
 33  \w    -31.00  30.00   0.50    5.73    --  -40.58  25.00 120.00  122
 34  \w   -108.00 -17.00   0.50    5.73    --  -40.58 -64.00 120.00  182
 35  \w   -109.00 -14.00   0.50    5.73    --  -40.58 -77.00 -90.00  190
 36  \w     41.00 100.00   0.50    5.73    --   40.58-138.00 -60.00  118
 37  \w     14.00 109.00   0.50    5.73    --   40.58  77.00  90.00  190
 38  \w     14.00 109.00   0.50    5.73    --   40.58  77.00 -90.00  190
 39  \w     14.00 109.00   0.50    5.73    --   40.58  77.00  30.00  190
 40  \w     83.00 142.00   0.50   22.93    --   96.35  33.00  60.00  118
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB Synergy, Dualflex, HyPix3000'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0358
_diffrn_reflns_av_unetI/netI     0.0194
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       34
_diffrn_reflns_limit_h_min       -33
_diffrn_reflns_limit_k_max       34
_diffrn_reflns_limit_k_min       -34
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            111414
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        66.598
_diffrn_reflns_theta_max         66.598
_diffrn_reflns_theta_min         3.062
_exptl_absorpt_coefficient_mu    2.707
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.61406
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.41.105a (Rigaku Oxford Diffraction, 2021)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear bluish green'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   bluish
_exptl_crystal_colour_primary    green
_exptl_crystal_density_diffrn    1.124
_exptl_crystal_description       block
_exptl_crystal_F_000             4416
_exptl_crystal_preparation       'solvent diffusion'
_exptl_crystal_size_max          0.0124
_exptl_crystal_size_mid          0.0122
_exptl_crystal_size_min          0.0118
_refine_diff_density_max         0.588
_refine_diff_density_min         -0.483
_refine_diff_density_rms         0.051
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.057
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     696
_refine_ls_number_reflns         10676
_refine_ls_number_restraints     728
_refine_ls_restrained_S_all      1.032
_refine_ls_R_factor_all          0.0559
_refine_ls_R_factor_gt           0.0492
_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^)+(0.0704P)^2^+9.3282P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1313
_refine_ls_wR_factor_ref         0.1364
_reflns_Friedel_coverage         0.000
_reflns_number_gt                9482
_reflns_number_total             10676
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6dt00079g2.cif
_cod_data_source_block           cm_al05_auto_cm01
_cod_depositor_comments
'Adding full bibliography for 7720145--7720151.cif.'
_cod_original_cell_volume        12079.79(12)
_cod_original_sg_symbol_H-M      'P 42/n'
_cod_database_code               7720151
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   0.969
_shelx_estimated_absorpt_t_min   0.967
_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
 N3-C14
 1.42 with sigma of 0.002
 N3-C15
 1.42 with sigma of 0.002
 N7-C41 = N7-C42
 1.42 with sigma of 0.002
 N7-C43
 1.42 with sigma of 0.002
 N3-C17
 1.42 with sigma of 0.002
 N3-C14 \\sim N3-C15
 with sigma of 0.04
 N7-C43 \\sim N7-C44
 with sigma of 0.04
 C46-C44 \\sim C43-C45
 with sigma of 0.04
 N3-C17 \\sim N3-C18
 with sigma of 0.04
 N3-C18 \\sim N3-C17
 with sigma of 0.04
 C20-C17 \\sim C18-C19
 with sigma of 0.04
 C48-C50 \\sim C47-C49
 with sigma of 0.02
 N7-C50 \\sim N7-C49
 with sigma of 0.04
 N7-C48 \\sim N7-C47
 with sigma of 0.04
 C50-C48 \\sim C49-C47
 with sigma of 0.04
 C41-N7 \\sim C41-N8
 with sigma of 0.02
 C42-N7 \\sim C42-N8
 with sigma of 0.02
 N7-C43 \\sim N8-C43
 with sigma of 0.02
 N7-C44 \\sim N8-C44
 with sigma of 0.02
 N7-C48 \\sim N8-C48
 with sigma of 0.02
 N7-C47 \\sim N8-C47
 with sigma of 0.02
 K2-N7 \\sim K2-N8
 with sigma of 0.04
 C41-C40 \\sim C41-C39
 with sigma of 0.02
 C42-C40 \\sim C42-C39
 with sigma of 0.02
 N6-C40 \\sim N6-C39
 with sigma of 0.04
 C42-C39 \\sim C41-C40
 with sigma of 0.04
3. Rigid body (RIGU) restrains
 All non-hydrogen atoms
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
4. Others
 Sof(C42)=Sof(H42A)=Sof(H42B)=Sof(C44)=Sof(H44A)=Sof(H44B)=Sof(C46)=Sof(H46A)=
 Sof(H46B)=Sof(H46C)=Sof(C19)=Sof(H19A)=Sof(H19B)=Sof(H19C)=Sof(C18)=Sof(H18A)=
 Sof(H18B)=1-FVAR(1)
 Sof(C41)=Sof(H41A)=Sof(H41B)=Sof(C43)=Sof(H43A)=Sof(H43B)=Sof(C45)=Sof(H45A)=
 Sof(H45B)=Sof(H45C)=Sof(C17)=Sof(H17A)=Sof(H17B)=Sof(C20)=Sof(H20A)=Sof(H20B)=
 Sof(H20C)=FVAR(1)
 Sof(N8)=1-FVAR(2)
 Sof(N7)=FVAR(2)
 Sof(C39)=Sof(H39A)=Sof(H39B)=1-FVAR(3)
 Sof(C40)=Sof(H40A)=Sof(H40B)=FVAR(3)
 Fixed Sof: C48(0.8) H48A(0.8) H48B(0.8) C50(0.8) H50A(0.8) H50B(0.8)
 H50C(0.8) C47(0.2) H47A(0.2) H47B(0.2) C49(0.2) H49A(0.2) H49B(0.2) H49C(0.2)
5.a Secondary CH2 refined with riding coordinates:
 C12(H12A,H12B), C13(H13A,H13B), C14(H14A,H14B), C38(H38A,H38B), C15(H15A,
 H15B), C41(H41A,H41B), C42(H42A,H42B), C43(H43A,H43B), C44(H44A,H44B),
 C17(H17A,H17B), C18(H18A,H18B), C48(H48A,H48B), C47(H47A,H47B), C40(H40A,H40B),
  C39(H39A,H39B)
5.b Aromatic/amide H refined with riding coordinates:
 C2(H2), C30(H30), C4(H4), C3(H3), C7(H7), C33(H33), C28(H28), C11(H11),
 C8(H8), C29(H29), C34(H34), C37(H37), C35(H35), C9(H9), C36(H36), C10(H10)
5.c Idealised Me refined as rotating group:
 C51(H51A,H51B,H51C), C55(H55A,H55B,H55C), C56(H56A,H56B,H56C), C52(H52A,H52B,
 H52C), C53(H53A,H53B,H53C), C54(H54A,H54B,H54C), C21(H21A,H21B,H21C), C16(H16A,
 H16B,H16C), C22(H22A,H22B,H22C), C23(H23A,H23B,H23C), C24(H24A,H24B,H24C),
 C26(H26A,H26B,H26C), C25(H25A,H25B,H25C), C45(H45A,H45B,H45C), C46(H46A,H46B,
 H46C), C20(H20A,H20B,H20C), C19(H19A,H19B,H19C), C50(H50A,H50B,H50C), C49(H49A,
 H49B,H49C)
;
_shelx_res_checksum              61297
_olex2_submission_special_instructions 'No special instructions were received'
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;