# Supplementary Information (SI) for Dalton Transactions.
# This journal is © The Royal Society of Chemistry 2026

####################################################################### 
# 
# This file contains crystal structure data downloaded from the 
# Cambridge Structural Database (CSD) hosted by the Cambridge 
# Crystallographic Data Centre (CCDC).
# 
# Full information about CCDC data access policies and citation 
# guidelines are available at http://www.ccdc.cam.ac.uk/access/V1 
# 
# Audit and citation data items may have been added by the CCDC. 
# Please retain this information to preserve the provenance of 
# this file and to allow appropriate attribution of the data. 
# 
#######################################################################

data_gtx18
_database_code_depnum_ccdc_archive 'CCDC 2404719'
loop_
_audit_author_name
_audit_author_address
'Giulia Taini'
;University of Milan
Italy
;
_audit_update_record             
;
2025-12-04 deposited with the CCDC.	2025-12-12 downloaded from the CCDC.
;

# start Validation Reply Form
_vrf_PLAT341_gtx18               
;
PROBLEM: Low Bond Precision on  C-C Bonds ...............    0.00725 Ang.  
RESPONSE: The disordered structure, namely around the [FeCl4]2- anion, leads to
a decrease in data quality, R(int) = 10.2%.
;
_vrf_PLAT299_gtx18               
;
PROBLEM: Atom Site Occupancy Constrained at .............        0.5 Check 
              Fe13    Cl14    Cl15    Cl16                                      
RESPONSE: The s.o.f. of the disordered [FeCl4]2- anion was constrained to
account for the symmetry-generated doubling of the sites.
;
_vrf_PLAT794_gtx18               
;
PROBLEM: Tentative Bond Valency for Fe1       (II)      .       2.25 Info  
RESPONSE: The Fe1 site has oxidation state (III), resulting in a positively
charged complex, balanced by the [FeCl4]2- anion, which features an iron(II)
center (Fe13).
;
# end Validation Reply Form

_audit_creation_method           SHELXL-2019/3
_shelx_SHELXL_version_number     2019/3
_chemical_name_common            n/a
_chemical_name_systematic        n/a
_chemical_formula_moiety         '2(C11 H18 Cl2 Fe N4), Cl4 Fe'
_chemical_formula_sum            'C22 H36 Cl8 Fe3 N8'
_chemical_formula_weight         863.74

loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0181 0.0091 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
N N 0.0311 0.0180 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0492 0.0322 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Cl Cl 0.3639 0.7018 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Fe Fe -1.1336 3.1974 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_space_group_crystal_system      monoclinic
_space_group_IT_number           12
_space_group_name_H-M_alt        'C 1 2/m 1'
_space_group_name_Hall           '-C 2y'

_shelx_space_group_comment       
;
The symmetry employed for this shelxl refinement is uniquely defined
by the following loop, which should always be used as a source of
symmetry information in preference to the above space-group names.
They are only intended as comments.
;

loop_
_space_group_symop_id
_space_group_symop_operation_xyz
1 x,y,z
2 -x,y,-z
3 -x,-y,-z
4 x,-y,z
5 x+1/2,y+1/2,z
6 -x+1/2,y+1/2,-z
7 -x+1/2,-y+1/2,-z
8 x+1/2,-y+1/2,z

_cell_length_a                   27.7537(10)
_cell_length_b                   8.7587(4)
_cell_length_c                   7.0757(3)
_cell_angle_alpha                90
_cell_angle_beta                 90.105(4)
_cell_angle_gamma                90
_cell_volume                     1720.00(12)
_cell_formula_units_Z            2
_cell_measurement_reflns_used    3538
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      79.5770
_cell_measurement_theta_min      3.1820
_exptl_absorpt_coefficient_mu    15.966
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.535
_exptl_absorpt_correction_type   gaussian
_exptl_absorpt_process_details   
;
CrysAlisPro 1.171.42.54a (Rigaku Oxford Diffraction, 2022)
Numerical absorption correction based on gaussian integration over
a multifaceted crystal model
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear dark brown'
_exptl_crystal_density_diffrn    1.668
_exptl_crystal_description       plate
_exptl_crystal_F_000             527.486
_exptl_crystal_size_max          0.38
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.07
_diffrn_reflns_av_R_equivalents  0.1024
_diffrn_reflns_av_unetI/netI     0.0473
_diffrn_reflns_Laue_measured_fraction_full 0.9988
_diffrn_reflns_Laue_measured_fraction_max 0.9802
_diffrn_reflns_limit_h_max       34
_diffrn_reflns_limit_h_min       -35
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            15600
_diffrn_reflns_point_group_measured_fraction_full 0.9988
_diffrn_reflns_point_group_measured_fraction_max 0.9802
_diffrn_reflns_theta_full        67.6840
_diffrn_reflns_theta_max         80.67
_diffrn_reflns_theta_min         3.18
_diffrn_ambient_temperature      150.00(10)
_diffrn_ambient_environment      N~2~
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'PhotonJet (Cu) X-ray Source'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_radiation_monochromator  mirror
_diffrn_measurement_method       'ω scans'
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB Synergy, Dualflex, HyPix'
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_type            HyPix
_diffrn_detector_area_resol_mean 10.0000
_diffrn_reflns_av_sigmaI/netI    0.0910
_diffrn_measured_fraction_theta_max 0.980
_diffrn_measured_fraction_theta_full 0.999
_reflns_number_total             1977
_reflns_number_gt                1602
_reflns_threshold_expression     'I > 2σ(I)'
_reflns_Friedel_coverage         0.890
_reflns_Friedel_fraction_max     0.874
_reflns_Friedel_fraction_full    0.932

_reflns_special_details          
;
 Reflections were merged by SHELXL according to the crystal
 class for the calculation of statistics and refinement.
 
 _reflns_Friedel_fraction is defined as the number of unique
 Friedel pairs measured divided by the number that would be
 possible theoretically, ignoring centric projections and
 systematic absences. Completness statistics refer to single and
 composite reflections containing twin component 1 only.
;

_computing_molecular_graphics    'DIAMOND (Brandenburg et al., 1999)'
_computing_data_collection       
'CrysAlisPro 1.171.42.54a (Rigaku Oxford Diffraction, 2022)'
_computing_structure_refinement  'SHELXL-2019/2 (Sheldrick, 2019)'
_computing_structure_solution    'SHELXT 2015 (Sheldrick, 2015)'
_refine_diff_density_max         0.9170
_refine_diff_density_min         -0.6335
_refine_diff_density_rms         0.1491
_refine_ls_d_res_high            0.7812
_refine_ls_d_res_low             13.8768
_refine_ls_goodness_of_fit_ref   1.0324
_refine_ls_matrix_type           full
_refine_ls_number_constraints    17
_refine_ls_number_parameters     118
_refine_ls_number_reflns         1977
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0839
_refine_ls_R_factor_gt           0.0676
_refine_ls_restrained_S_all      1.0324
_refine_ls_shift/su_max          -0.0005
_refine_ls_shift/su_mean         0.0001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     
'w=1/[σ²(Fo²)+(0.0997P)²+7.6984P] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_primary     dual
_atom_sites_solution_secondary   ?
_atom_sites_solution_hydrogens   geom
_refine_ls_hydrogen_treatment    mixed
_refine_ls_extinction_method     none
_refine_ls_extinction_coef       .

_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1715
_refine_ls_wR_factor_ref         0.1914

_refine_special_details          
;The disordered [FeCl4]2- moiety was refined with fixed s.o.f.: Fe13(0.25)
Cl14(0.5) Cl15(0.25) Cl16(0.25). Hydrogen atoms were refined with fixed Uiso at
1.2 times of all C(H), C(H,H), and N(H) groups:
a Aromatic/amide H refined with riding coordinates: C11(H11), C12(H12)
b Secondary CH2 refined with riding coordinates: C6(H6a,H6b), C7(H7a,H7b),
C9(H9a,H9b)
b Ternary CH refined with riding coordinates: N4(H4), N8(H8),Disordered [FeCl4]2- anion refined with fixed occupancies.
;

loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_occupancy
_atom_site_site_symmetry_order
_atom_site_refinement_flags_posn
_atom_site_refinement_flags_adp
_atom_site_refinement_flags_occupancy
Fe1 Fe 0.70249(3) 0.5 0.62758(15) 0.0341(3) Uani 1.000000 2 S T P
Cl2 Cl 0.73020(6) 0.5 0.3093(3) 0.0450(4) Uani 1.000000 2 S T P
Cl3 Cl 0.77921(6) 0.5 0.7539(3) 0.0477(5) Uani 1.000000 2 S T P
N4 N 0.6705(2) 0.5 0.9085(9) 0.0462(15) Uani 1.000000 2 S T P
H4 H 0.6958(2) 0.5 0.9947(9) 0.0555(18) Uiso 1.000000 2 RS T P
N5 N 0.63068(18) 0.5 0.5201(8) 0.0355(12) Uani 1.000000 2 S T P
C6 C 0.64328(19) 0.3588(7) 0.9402(8) 0.0517(14) Uani 1.000000 1 . . .
H6a H 0.63903(19) 0.3412(7) 1.0773(8) 0.0620(16) Uiso 1.000000 1 R . .
H6b H 0.61102(19) 0.3665(7) 0.8810(8) 0.0620(16) Uiso 1.000000 1 R . .
C7 C 0.6712(2) 0.2284(7) 0.8532(9) 0.0574(15) Uani 1.000000 1 . . .
H7a H 0.7024(2) 0.2163(7) 0.9196(9) 0.0689(18) Uiso 1.000000 1 R . .
H7b H 0.6528(2) 0.1323(7) 0.8671(9) 0.0689(18) Uiso 1.000000 1 R . .
N8 N 0.67984(15) 0.2594(5) 0.6507(7) 0.0456(10) Uani 1.000000 1 . . .
H8 H 0.70539(15) 0.1985(5) 0.6116(7) 0.0548(13) Uiso 1.000000 1 R . .
C9 C 0.6382(2) 0.2265(6) 0.5269(9) 0.0526(14) Uani 1.000000 1 . . .
H9a H 0.6498(2) 0.1796(6) 0.4082(9) 0.0631(17) Uiso 1.000000 1 R . .
H9b H 0.6169(2) 0.1519(6) 0.5903(9) 0.0631(17) Uiso 1.000000 1 R . .
C10 C 0.60970(16) 0.3669(6) 0.4802(7) 0.0394(11) Uani 1.000000 1 . . .
C11 C 0.56483(18) 0.3640(7) 0.3915(8) 0.0528(14) Uani 1.000000 1 . . .
H11 H 0.54951(18) 0.2698(7) 0.3626(8) 0.0633(17) Uiso 1.000000 1 R . .
C12 C 0.5434(3) 0.5 0.3471(12) 0.058(2) Uani 1.000000 2 S T P
H12 H 0.5131(3) 0.4999999999999999 0.2843(12) 0.069(3) Uiso 1.000000 2 RS T P
Fe13 Fe 0.51192(7) 1.0 -0.0032(5) 0.0516(7) Uani 0.500000 2 S T P
Cl14 Cl 0.47248(15) 0.7951(6) 0.0829(7) 0.1140(19) Uani 0.500000 1 . . P
Cl15 Cl 0.52111(17) 1.0 -0.3129(7) 0.0676(12) Uani 0.500000 2 S T P
Cl16 Cl 0.58239(12) 1.0 0.1356(6) 0.0490(9) Uani 0.500000 2 S T P


loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_2
_geom_bond_publ_flag
Fe1 Cl2 2.381(2) . ?
Fe1 Cl3 2.3077(17) . ?
Fe1 N4 2.179(6) . ?
Fe1 N5 2.132(5) . ?
Fe1 N8 2.205(4) 4_565 ?
Fe1 N8 2.205(4) . ?
N4 H4 0.9300 . ?
N4 C6 1.466(6) 4_565 ?
N4 C6 1.466(6) . ?
N5 C10 1.333(5) 4_565 ?
N5 C10 1.333(5) . ?
C6 H6a 0.9900 . ?
C6 H6b 0.9900 . ?
C6 C7 1.512(8) . ?
C7 H7a 0.9900 . ?
C7 H7b 0.9900 . ?
C7 N8 1.478(8) . ?
N8 H8 0.9300 . ?
N8 C9 1.478(7) . ?
C9 H9a 0.9900 . ?
C9 H9b 0.9900 . ?
C9 C10 1.498(8) . ?
C10 C11 1.394(7) . ?
C11 H11 0.9500 . ?
C11 C12 1.368(7) 4_565 ?
C12 H12 0.9500 . ?
Fe13 Fe13 0.663(4) 2_655 ?
Fe13 Cl14 1.931(5) 3_675 ?
Fe13 Cl14 2.189(4) 4_575 ?
Fe13 Cl14 2.189(4) . ?
Fe13 Cl14 1.931(5) 2_655 ?
Fe13 Cl15 2.419(6) 2_655 ?
Fe13 Cl15 2.207(6) . ?
Fe13 Cl16 2.187(4) . ?
Cl14 Cl14 1.927(10) 2_655 ?
Cl14 Cl15 2.429(7) 3_675 ?

loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_3
_geom_angle_publ_flag
Cl3 Fe1 Cl2 93.84(7) . . ?
N4 Fe1 Cl2 174.78(17) . . ?
N4 Fe1 Cl3 91.39(17) . . ?
N5 Fe1 Cl2 88.05(16) . . ?
N5 Fe1 Cl3 178.12(17) . . ?
N5 Fe1 N4 86.7(2) . . ?
N8 Fe1 Cl2 99.37(13) 4_565 . ?
N8 Fe1 Cl2 99.37(13) . . ?
N8 Fe1 Cl3 103.55(11) 4_565 . ?
N8 Fe1 Cl3 103.55(11) . . ?
N8 Fe1 N4 79.37(13) 4_565 . ?
N8 Fe1 N4 79.37(13) . . ?
N8 Fe1 N5 76.11(11) . . ?
N8 Fe1 N5 76.11(11) 4_565 . ?
N8 Fe1 N8 145.7(2) . 4_565 ?
H4 N4 Fe1 106.79(16) . . ?
C6 N4 Fe1 110.5(3) . . ?
C6 N4 Fe1 110.5(3) 4_565 . ?
C6 N4 H4 106.8(3) . . ?
C6 N4 H4 106.8(3) 4_565 . ?
C6 N4 C6 115.0(6) . 4_565 ?
C10 N5 Fe1 118.9(3) 4_565 . ?
C10 N5 Fe1 118.9(3) . . ?
C10 N5 C10 122.0(6) . 4_565 ?
H6a C6 N4 110.1(3) . 4_565 ?
H6b C6 N4 110.1(3) . 4_565 ?
H6b C6 H6a 108.4 . . ?
C7 C6 N4 108.1(4) . 4_565 ?
C7 C6 H6a 110.1(3) . . ?
C7 C6 H6b 110.1(3) . . ?
H7a C7 C6 109.7(3) . . ?
H7b C7 C6 109.7(3) . . ?
H7b C7 H7a 108.2 . . ?
N8 C7 C6 109.9(4) . . ?
N8 C7 H7a 109.7(3) . . ?
N8 C7 H7b 109.7(3) . . ?
C7 N8 Fe1 107.1(4) . 4_565 ?
H8 N8 Fe1 107.95(11) . 4_565 ?
H8 N8 C7 108.0(3) . . ?
C9 N8 Fe1 111.4(3) . 4_565 ?
C9 N8 C7 114.3(5) . . ?
C9 N8 H8 108.0(3) . . ?
H9a C9 N8 109.1(3) . . ?
H9b C9 N8 109.1(3) . . ?
H9b C9 H9a 107.8 . . ?
C10 C9 N8 112.5(4) . . ?
C10 C9 H9a 109.1(3) . . ?
C10 C9 H9b 109.1(3) . . ?
C9 C10 N5 116.2(4) . 4_565 ?
C11 C10 N5 120.1(5) . 4_565 ?
C11 C10 C9 123.7(5) . . ?
H11 C11 C10 120.8(3) . . ?
C12 C11 C10 118.3(5) 4_565 . ?
C12 C11 H11 120.8(3) 4_565 . ?
C11 C12 C11 121.2(7) . 4_565 ?
H12 C12 C11 119.4(3) . 4_565 ?
H12 C12 C11 119.4(3) . . ?
Cl14 Fe13 Cl14 110.1(3) 4_575 . ?
Cl14 Fe13 Cl14 55.4(3) 4_575 3_675 ?
Cl14 Fe13 Cl14 55.4(3) 2_655 . ?
Cl14 Fe13 Cl14 136.8(4) 2_655 3_675 ?
Cl15 Fe13 Cl14 109.57(19) . 4_575 ?
Cl15 Fe13 Cl14 71.6(2) . 2_655 ?
Cl15 Fe13 Cl14 110.8(2) 2_655 3_675 ?
Cl15 Fe13 Cl14 63.40(19) 2_655 . ?
Cl15 Fe13 Cl14 109.57(19) . . ?
Cl15 Fe13 Cl14 71.6(2) . 3_675 ?
Cl15 Fe13 Cl14 110.8(2) 2_655 2_655 ?
Cl15 Fe13 Cl14 63.40(19) 2_655 4_575 ?
Cl16 Fe13 Cl14 108.80(15) . . ?
Cl16 Fe13 Cl14 108.80(15) . 4_575 ?
Cl16 Fe13 Cl14 86.00(13) . 3_675 ?
Cl16 Fe13 Cl14 86.00(13) . 2_655 ?
Cl16 Fe13 Cl15 109.9(2) . . ?
Cl16 Fe13 Cl15 85.7(2) . 2_655 ?
Cl14 Cl14 Fe13 55.50(15) 2_655 4_575 ?
Cl14 Cl14 Fe13 69.14(17) 2_655 3_675 ?
Cl15 Cl14 Fe13 62.91(19) 3_675 4_575 ?
Cl15 Cl14 Fe13 59.5(2) 3_675 3_675 ?
Cl14 Cl15 Fe13 53.68(14) 3_675 2_655 ?
Cl14 Cl15 Fe13 48.93(13) 3_675 . ?
Cl14 Cl15 Fe13 53.68(14) 2_655 2_655 ?
Cl14 Cl15 Fe13 48.93(13) 2_655 . ?
Cl14 Cl15 Cl14 95.3(3) 2_655 3_675 ?

loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
_geom_torsion
_geom_torsion_site_symmetry_1
_geom_torsion_site_symmetry_2
_geom_torsion_site_symmetry_3
_geom_torsion_site_symmetry_4
_geom_torsion_publ_flag
Fe1 N4 C6 C7 -39.2(4) . . 4_565 4_565 ?
Fe1 N4 C6 C7 39.2(4) . . . . ?
Fe1 N5 C10 C9 -3.7(5) . . 4_565 4_565 ?
Fe1 N5 C10 C9 3.7(5) . . . . ?
Fe1 N5 C10 C11 173.3(4) . . 4_565 4_565 ?
Fe1 N5 C10 C11 -173.3(4) . . . . ?
Fe1 N8 C7 C6 44.2(3) . . . . ?
Fe1 N8 C9 C10 -23.3(3) . . . . ?
N4 C6 C7 N8 -56.6(5) . . . . ?
N5 C10 C9 N8 13.7(5) . . . . ?
N5 C10 C11 C12 -0.1(7) . 4_565 4_565 . ?
N5 C10 C11 C12 0.1(7) . . . . ?
C6 N4 C6 C7 165.1(6) 4_565 . . . ?
C6 C7 N8 C9 -79.7(5) . . . . ?
C7 N8 C9 C10 98.2(5) . . . . ?
N8 C9 C10 C11 -169.5(4) . . . . ?
C9 C10 N5 C10 178.0(6) . . . 4_565 ?
C9 C10 C11 C12 -176.6(7) . . . . ?
C10 N5 C10 C11 1.1(7) 4_565 . . . ?
C10 C11 C12 C11 -1.3(3) . . . 4_565 ?
Cl14 Fe13 Fe13 Cl14 -146.9(3) 4_575 . 2_655 . ?
Cl14 Fe13 Fe13 Cl14 180.0(4) 3_675 . 2_655 . ?
Cl14 Fe13 Fe13 Cl14 33.1(3) . 3_675 . 2_655 ?
Cl14 Fe13 Fe13 Cl14 -33.1(8) . . 3_675 2_655 ?
Cl14 Fe13 Fe13 Cl14 -180.0(4) 3_675 2_655 . . ?
Cl14 Fe13 Fe13 Cl14 146.9(8) 4_575 2_655 . . ?
Cl14 Fe13 Fe13 Cl15 -73.5(3) 3_675 2_655 . . ?
Cl14 Fe13 Fe13 Cl15 -106.5(3) 4_575 2_655 . . ?
Cl14 Fe13 Fe13 Cl15 73.5(3) 3_675 . 2_655 . ?
Cl14 Fe13 Fe13 Cl15 106.5(3) 4_575 . 2_655 . ?
Cl14 Fe13 Fe13 Cl16 73.5(3) 4_575 2_655 . . ?
Cl14 Fe13 Fe13 Cl16 106.5(3) 3_675 2_655 . . ?
Cl15 Fe13 Fe13 Cl14 -73.47(18) . 2_655 . 2_655 ?
Cl15 Fe13 Fe13 Cl14 73.5(5) . . 2_655 2_655 ?
Cl15 Fe13 Fe13 Cl14 106.53(18) . . 2_655 . ?
Cl15 Fe13 Fe13 Cl14 -106.5(5) . 2_655 . . ?
Cl15 Fe13 Fe13 Cl15 180.0 . 2_655 . 2_655 ?
Cl15 Fe13 Fe13 Cl15 180.0 . . 2_655 2_655 ?
Cl15 Fe13 Fe13 Cl16 180.0 . 2_655 . . ?
Cl15 Fe13 Fe13 Cl16 0.0 . . 2_655 2_655 ?
Cl16 Fe13 Fe13 Cl14 -73.47(18) . . 2_655 . ?
Cl16 Fe13 Fe13 Cl14 -106.5(5) . . 2_655 2_655 ?
Cl16 Fe13 Fe13 Cl15 0.0 . . 2_655 2_655 ?
Cl16 Fe13 Fe13 Cl16 180.0 . . 2_655 2_655 ?


_chemical_melting_point          n/a
_exptl_crystal_recrystallization_method 
'Slow solvent diffusion, diethyl ether/methanol (v/v 1:1)'
