# Supplementary Material (ESI) for Chemical Communications
# This journal is (c) The Royal Society of Chemistry 2009

data_global
_journal_name_full               Chem.Commun.

_journal_coden_Cambridge         0182

_publ_contact_author_name        'Thomas Groshens'
_publ_contact_author_email       THOMAS.GROSHENS@NAVY.MIL

_publ_section_title              
;
New Hydrogen Storage Materials Exploiting the
Self-Sustaining Thermal Decomposition of Guanidinium Borohydride
;
loop_
_publ_author_name
'Thomas Groshens'
'Richard A Hollins'

# Attachment 'Updated CCDC 705066.cif.txt'

data_tg_gbh2_0m
_database_code_depnum_ccdc_archive 'CCDC 705066'

_audit_creation_method           SHELXL-97
_chemical_name_systematic        'Guanidinium Tetrahydroborate'
_chemical_name_common            'Guanidinium Tetrahydroborate'
_chemical_formula_moiety         'C H6 N3, B H4'
_chemical_formula_sum            'C H10 B N3'
_exptl_crystal_recrystallization_method 'From Isopropanol'
_chemical_melting_point          ?

_exptl_crystal_description       'Tetragonal Bipyrimide'
_exptl_crystal_colour            Colourless

_diffrn_ambient_temperature      296(2)
_chemical_formula_weight         74.93

loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0033 0.0016 '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'
B B 0.0013 0.0007 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
N N 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_H-M   'I 41/a m d'
_symmetry_int_tables_number      141
_symmetry_space_group_name_Hall  '-I 4bd 2'

loop_
_symmetry_equiv_pos_as_xyz
'x, y, z'
'-y+1/4, x+3/4, z+1/4'
'y+1/4, -x+1/4, z+3/4'
'x, -y, -z'
'-x, y+1/2, -z'
'-x, -y+1/2, z'
'y+1/4, x+3/4, -z+1/4'
'-y+1/4, -x+1/4, -z+3/4'
'x+1/2, y+1/2, z+1/2'
'-y+3/4, x+5/4, z+3/4'
'y+3/4, -x+3/4, z+5/4'
'x+1/2, -y+1/2, -z+1/2'
'-x+1/2, y+1, -z+1/2'
'-x+1/2, -y+1, z+1/2'
'y+3/4, x+5/4, -z+3/4'
'-y+3/4, -x+3/4, -z+5/4'
'-x, -y, -z'
'y-1/4, -x-3/4, -z-1/4'
'-y-1/4, x-1/4, -z-3/4'
'-x, y, z'
'x, -y-1/2, z'
'x, y-1/2, -z'
'-y-1/4, -x-3/4, z-1/4'
'y-1/4, x-1/4, z-3/4'
'-x+1/2, -y+1/2, -z+1/2'
'y+1/4, -x-1/4, -z+1/4'
'-y+1/4, x+1/4, -z-1/4'
'-x+1/2, y+1/2, z+1/2'
'x+1/2, -y, z+1/2'
'x+1/2, y, -z+1/2'
'-y+1/4, -x-1/4, z+1/4'
'y+1/4, x+1/4, z-1/4'

_cell_length_a                   6.7433(8)
_cell_length_b                   6.7433(8)
_cell_length_c                   24.195(3)
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_volume                     1100.2(2)
_cell_formula_units_Z            8
_cell_measurement_temperature    296(2)
_cell_measurement_reflns_used    4900
_cell_measurement_theta_min      3.136
_cell_measurement_theta_max      24.435
_exptl_crystal_size_max          0.31
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_exptl_crystal_density_diffrn    0.905
#Calc. density is consistant with similar high percent hydrogen atom compounds
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             336
_exptl_absorpt_coefficient_mu    0.060
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_correction_T_min  0.9816
_exptl_absorpt_correction_T_max  0.9890
_exptl_absorpt_process_details   multiscan

_exptl_special_details           
;
?
;
_diffrn_radiation_probe          ?
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_source                   'fine-focus sealed tube'
_diffrn_radiation_monochromator  graphite
_diffrn_measurement_device_type  'Bruker SMART APEXII'
_diffrn_measurement_method       CCD
_diffrn_detector_area_resol_mean ?
_diffrn_reflns_number            4900
_diffrn_reflns_av_R_equivalents  0.0179
_diffrn_reflns_av_sigmaI/netI    0.0078
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_l_min       -28
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_theta_min         3.14
_diffrn_reflns_theta_max         25.00
_reflns_number_total             287
_reflns_number_gt                235
_reflns_threshold_expression     >2sigma(I)

_computing_data_collection       ?
_computing_cell_refinement       'Bruker SHELXTL Software Package'
_computing_data_reduction        ?
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_molecular_graphics    ?
_computing_publication_material  ?

_refine_special_details          
;
Refinement of F^2^ against ALL reflections. The weighted R-factor wR and
goodness of fit S are based on F^2^, conventional R-factors R are based
on F, with F set to zero for negative F^2^. The threshold expression of
F^2^ > 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is
not relevant to the choice of reflections for refinement. R-factors based
on F^2^ are statistically about twice as large as those based on F, and R-
factors based on ALL data will be even larger.
;

_refine_ls_structure_factor_coef Fsqd
_refine_ls_matrix_type           full
_refine_ls_weighting_scheme      calc
_refine_ls_weighting_details     
'calc w=1/[\s^2^(Fo^2^)+(0.0906P)^2^+0.1181P] where P=(Fo^2^+2Fc^2^)/3'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_atom_sites_solution_hydrogens   geom
_refine_ls_hydrogen_treatment    mixed
_refine_ls_extinction_method     none
_refine_ls_extinction_coef       0.0180(70)
_refine_ls_number_reflns         287
_refine_ls_number_parameters     28
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0597
_refine_ls_R_factor_gt           0.0545
_refine_ls_wR_factor_ref         0.1559
_refine_ls_wR_factor_gt          0.1461
_refine_ls_goodness_of_fit_ref   1.180
_refine_ls_restrained_S_all      1.180
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000

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_symmetry_multiplicity
_atom_site_calc_flag
_atom_site_refinement_flags
_atom_site_disorder_assembly
_atom_site_disorder_group
B1 B 0.5000 0.7500 0.07976(16) 0.1080(16) Uani 1 4 d S . .
N1 N 0.8315(2) 0.7500 0.96431(7) 0.0919(8) Uani 1 2 d S . .
H2 H 0.7211 0.7500 0.9821 0.110 Uiso 1 2 calc SR . .
H1 H 0.8315 0.7500 0.9288 0.110 Uiso 1 2 calc SR . .
N2 N 1.0000 0.7500 1.04534(10) 0.0883(9) Uani 1 4 d S . .
C1 C 1.0000 0.7500 0.99142(11) 0.0694(9) Uani 1 4 d S . .
H5 H 0.368(5) 0.7500 0.1041(15) 0.166(12) Uiso 1 2 d S . .
H4 H 0.5000 0.656(5) 0.0412(17) 0.195(16) Uiso 1 2 d S . .
H3 H 1.109(3) 0.7500 1.0587(11) 0.102(8) Uiso 1 2 d S . .

loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_23
_atom_site_aniso_U_13
_atom_site_aniso_U_12
B1 0.0686(19) 0.192(5) 0.0637(18) 0.000 0.000 0.000
N1 0.0761(12) 0.1160(15) 0.0836(12) 0.000 -0.0062(7) 0.000
N2 0.0737(18) 0.118(2) 0.0732(16) 0.000 0.000 0.000
C1 0.0670(14) 0.0644(15) 0.0769(17) 0.000 0.000 0.000

_geom_special_details            
;
All esds (except the esd in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell esds are taken
into account individually in the estimation of esds in distances, angles
and torsion angles; correlations between esds in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell esds is used for estimating esds involving l.s. planes.
;

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
B1 H5 1.07(3) . ?
B1 H4 1.13(4) . ?
N1 H2 0.8600 . ?
N1 H1 0.8600 . ?
N2 C1 1.305(4) . ?
N2 H3 0.80(2) . ?
C1 N1 1.312(2) 20_755 ?

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
H5 B1 H4 117.2(15) . . ?
C1 N1 H2 120.0 . . ?
C1 N1 H1 120.0 . . ?
H2 N1 H1 120.0 . . ?
C1 N2 H3 113.8(19) . . ?
N2 C1 N1 120.00(12) . 20_755 ?
N1 C1 N1 120.0(2) . 20_755 ?

_diffrn_measured_fraction_theta_max 1.000
_diffrn_reflns_theta_full        25.00
_diffrn_measured_fraction_theta_full 1.000
_refine_diff_density_max         0.165
_refine_diff_density_min         -0.174
_refine_diff_density_rms         0.046