# Supplementary Material (ESI) for ChemComm
# This journal is © The Royal Society of Chemistry 2000
# CCDC Number: 182/1663

data_sxd1 
 
_audit_creation_method            SHELXL-97 
_publ_contact_author_name         'Dr. Thomas Steiner'
_publ_contact_author_address
; 
  Institut f\"ur Chemie - Kristallographie
  Freie Universit\"at Berlin
  Takustra\sse 6
  D-14195 Berlin
  Germany 
;
_publ_contact_author_email        steiner@chemie.fu-berlin.de

_publ_contact_letter
;
  Please consider this CIF as a supplement to submission B001179G
  for Chem.Commun.
;
_publ_requested_journal           'Chem. Commun.'

_publ_section_title
;
Neutron diffraction study of a very short O-H...n hydrogen bond:
crystalline adduct of 2-methylpyridine and pentachlorophenol
;

loop_
_publ_author_name
_publ_author_address
  'Steiner, Thomas'
;
  Institut f\"ur Chemie - Kristallographie
  Freie Universit\"at Berlin
  Takustr. 6
  D-14195 Berlin
  Germany
;
  'Wilson, Chick C.'
;  
   ISIS
   Rutherford-Appleton Laboratory
   Chilton, UK
;
  'Majerz, Irena'
; 
  Institute of Chemistry
  University of Wroclaw
  Poland
;

 
_chemical_name_systematic         
; 
 2-methylpyridine pentachlorophenol 
; 
_chemical_name_common             ? 
_chemical_melting_point           ? 
_chemical_formula_moiety          ? 
_chemical_formula_sum 
 'C12 H8 Cl5 N O' 
_chemical_formula_weight          359.47 
 
_symmetry_cell_setting            triclinic
_symmetry_space_group_name_H-M    'P -1' 
 
loop_ 
 _symmetry_equiv_pos_as_xyz 
 'x, y, z' 
 '-x, -y, -z' 
 
_cell_length_a                    9.276(5) 
_cell_length_b                    11.668(6) 
_cell_length_c                    6.849(4) 
_cell_angle_alpha                 104.61(3) 
_cell_angle_beta                  105.06(3) 
_cell_angle_gamma                 99.87(3) 
_cell_volume                      670.0(6) 
_cell_formula_units_Z             2 
_cell_measurement_temperature     30(1) 
_cell_measurement_reflns_used     25 
_cell_measurement_theta_min       ? 
_cell_measurement_theta_max       ? 
 
_exptl_crystal_description        'flat plate'
_exptl_crystal_colour             colourless 
_exptl_crystal_size_max           2.5 
_exptl_crystal_size_mid           2.0 
_exptl_crystal_size_min           1.0 
_exptl_crystal_density_meas       ? 
_exptl_crystal_density_diffrn     1.782 
_exptl_crystal_density_method     'not measured' 
_exptl_crystal_F_000              22.58 
_exptl_absorpt_coefficient_mu     '1.450, at 1 Angstrom' 
_exptl_absorpt_correction_type    empirical 
_exptl_absorpt_correction_T_min   0.49
_exptl_absorpt_correction_T_max   0.89 
_exptl_absorpt_process_details    
;
The linear absorption coefficient is wavelength dependent
 and it is calculated as: 
          mu = 0.49 + 0.96 * lambda  [cm^-1]
;
 
_exptl_special_details 
; 
For peak integration a local UB matrix refined for each frame, 
using approximately 25 reflections.
Hence _cell_measurement_reflns_used      25

For final cell dimensions an average of all local 
cells was performed and estimated standard uncertainties 
were obtained from the spread of the local observations

Because of the nature of the experiment, it is not possible to give values of
theta_min and theta_max for the cell determination.

Instead, we can give values of

_cell_measurement_sin(theta)/lambda_min      0.23
_cell_measurement_sin(theta)/lambda_max      1.04

The same applies for the wavelength used for the experiment.
The range of wavelengths used was 0.5-5.0 Angstroms,
BUT the bulk of the diffraction information is obtained from 
wavelengths in the range 0.7-2.5 Angstroms.

The data collection procedures on the SXD instrument used
for the single crystal neutron data collection are most
recently summarised in the Appendix to the following paper
     Wilson, C.C. (1997).  J. Mol. Struct. 405, 207-217.  
; 
 
_diffrn_ambient_temperature       30(1) 
_diffrn_radiation_wavelength      0.5-5.0
_diffrn_radiation_type            neutron 
_diffrn_radiation_source          'ISIS spallation source' 
_diffrn_radiation_monochromator   none 
_diffrn_measurement_device_type   SXD 
_diffrn_measurement_method        'time-of-flight LAUE diffraction' 
_diffrn_standards_number          ? 
_diffrn_standards_interval_count  ? 
_diffrn_standards_interval_time   ? 
_diffrn_standards_decay_%         ? 
_diffrn_reflns_number             12790 
_diffrn_reflns_av_R_equivalents   0.076
_diffrn_reflns_av_sigmaI/netI     0.043 
_diffrn_reflns_limit_h_min        0 
_diffrn_reflns_limit_h_max        27 
_diffrn_reflns_limit_k_min        -35 
_diffrn_reflns_limit_k_max        32 
_diffrn_reflns_limit_l_min        -18 
_diffrn_reflns_limit_l_max        16 
_diffrn_reflns_theta_min          ? 
_diffrn_reflns_theta_max          ? 
_reflns_number_total              4303 
_reflns_number_gt                 4303 
_reflns_threshold_expression      >2sigma(I) 
 
_computing_data_collection        ? 
_computing_cell_refinement        ? 
_computing_data_reduction         ? 
_computing_structure_solution     'SHELXS-97 (Sheldrick, 1990)' 
_computing_structure_refinement   'SHELXL-97 (Sheldrick, 1997)' 
_computing_molecular_graphics     ? 
_computing_publication_material   ? 
 
_refine_special_details 
; 
The variable wavelength nature of the data collection
procedure means that sensible values of 
_diffrn_reflns_theta_min & _diffrn_reflns_theta_max
cannot be given

It is also difficult to estimate realistic values of
maximum sin(theta)/lambda values for two reasons:
(i) Different sin(theta)/lambda ranges are accessed 
    in different parts of the detectors
(ii) The nature of the data collection occasionally 
     allows some reflections at very high sin(theta)/lambda 
     to be observed even when no real attempt has been 
     made to measure data in this region.

However, we can attempt to estimate the sin(theta)/lambda limits as follows:

_diffrn_reflns_sin(theta)/lambda_min      0.10
_diffrn_reflns_sin(theta)/lambda_max      1.28

Note also that reflections for which the standard profile fitting integration
procedure fails are excluded from the data set, thus resulting in a high
elimination rate of very weak or "unobserved" peaks from the final data set.

The extinction coefficient reported in _refine_ls_extinction_coef is in this 
case the refined value of the mosaic spread in units of 10^-4 rad^-1
The reference for the extinction method used is:
     Becker, P. & Coppens, P. (1974). Acta Cryst. A30, 129-148.

; 
 
_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^)+(0.1277P)^2^+30.3892P] 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      'Becker-Coppens Lorentzian model' 
_refine_ls_extinction_coef        0.160
_refine_ls_extinction_expression 
 'Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^' 
_refine_ls_number_reflns          4303 
_refine_ls_number_parameters      245 
_refine_ls_number_restraints      0 
_refine_ls_R_factor_all           0.0735 
_refine_ls_R_factor_gt            0.0735 
_refine_ls_wR_factor_ref          0.1830 
_refine_ls_wR_factor_gt           0.1830 
_refine_ls_goodness_of_fit_ref    1.023 
_refine_ls_restrained_S_all       1.023 
_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 
O O 0.7591(3) 0.3060(2) -0.0110(5) 0.0078(4) Uani 1 1 d . . . 
Cl2 Cl 0.87747(14) 0.09155(13) -0.0886(3) 0.0062(2) Uani 1 1 d . . . 
Cl3 Cl 0.62594(16) -0.15390(12) -0.2979(3) 0.0063(2) Uani 1 1 d . . . 
Cl4 Cl 0.27727(15) -0.15388(12) -0.3993(3) 0.0066(2) Uani 1 1 d . . . 
Cl5 Cl 0.18460(15) 0.09311(13) -0.2960(3) 0.0072(3) Uani 1 1 d . . . 
Cl6 Cl 0.43963(15) 0.33901(12) -0.1023(3) 0.0072(3) Uani 1 1 d . . . 
C1 C 0.6473(2) 0.20417(17) -0.0958(4) 0.0050(3) Uani 1 1 d . . . 
C2 C 0.6859(2) 0.09148(16) -0.1464(4) 0.0051(3) Uani 1 1 d . . . 
C3 C 0.5727(2) -0.01900(16) -0.2383(4) 0.0043(3) Uani 1 1 d . . . 
C4 C 0.41698(19) -0.01890(16) -0.2838(4) 0.0045(3) Uani 1 1 d . . . 
C5 C 0.3762(2) 0.09234(17) -0.2387(4) 0.0045(3) Uani 1 1 d . . . 
C6 C 0.4896(2) 0.20154(17) -0.1457(4) 0.0048(3) Uani 1 1 d . . . 
N1' N 0.76151(15) 0.47509(12) 0.3186(3) 0.0070(2) Uani 1 1 d . . . 
C2' C 0.8698(2) 0.58109(17) 0.3866(3) 0.0057(3) Uani 1 1 d . . . 
C3' C 0.8983(2) 0.66520(18) 0.5856(4) 0.0079(4) Uani 1 1 d . . . 
C4' C 0.8140(2) 0.6382(2) 0.7162(4) 0.0078(4) Uani 1 1 d . . . 
C5' C 0.7003(2) 0.5285(2) 0.6427(4) 0.0091(4) Uani 1 1 d . . . 
C6' C 0.6793(2) 0.4501(2) 0.4437(4) 0.0091(4) Uani 1 1 d . . . 
C7' C 0.9581(2) 0.6046(2) 0.2391(4) 0.0087(4) Uani 1 1 d . . . 
H H 0.7461(7) 0.3763(6) 0.1127(13) 0.0211(13) Uani 1 1 d . . . 
H3' H 0.9869(8) 0.7496(6) 0.6351(14) 0.0239(14) Uani 1 1 d . . . 
H4' H 0.8356(9) 0.7012(7) 0.8729(12) 0.0260(16) Uani 1 1 d . . . 
H5' H 0.6331(9) 0.5051(8) 0.7415(14) 0.0253(15) Uani 1 1 d . . . 
H6' H 0.5928(8) 0.3640(6) 0.3772(14) 0.0256(16) Uani 1 1 d . . . 
H71' H 0.9744(14) 0.6978(9) 0.238(2) 0.042(3) Uani 1 1 d . . . 
H72' H 0.8990(10) 0.5455(10) 0.0757(12) 0.0313(19) Uani 1 1 d . . . 
H73' H 1.0715(10) 0.5917(14) 0.290(2) 0.043(3) Uani 1 1 d . . . 
 
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 
O 0.0070(6) 0.0060(5) 0.0090(9) 0.0013(7) 0.0024(6) -0.0001(5) 
Cl2 0.0039(3) 0.0074(4) 0.0075(5) 0.0025(4) 0.0021(3) 0.0014(3) 
Cl3 0.0082(4) 0.0048(3) 0.0066(5) 0.0019(4) 0.0025(4) 0.0031(3) 
Cl4 0.0063(3) 0.0055(3) 0.0067(5) 0.0017(4) 0.0013(3) -0.0002(3) 
Cl5 0.0050(3) 0.0079(4) 0.0081(5) 0.0019(4) 0.0018(4) 0.0016(3) 
Cl6 0.0070(3) 0.0057(3) 0.0086(5) 0.0027(4) 0.0014(4) 0.0022(3) 
C1 0.0043(4) 0.0051(5) 0.0058(7) 0.0016(6) 0.0023(5) 0.0003(4) 
C2 0.0043(4) 0.0047(4) 0.0061(7) 0.0015(6) 0.0019(5) 0.0006(3) 
C3 0.0052(4) 0.0042(4) 0.0039(6) 0.0015(5) 0.0017(4) 0.0014(3) 
C4 0.0043(4) 0.0041(4) 0.0054(7) 0.0017(5) 0.0019(5) 0.0008(3) 
C5 0.0042(4) 0.0055(4) 0.0053(6) 0.0029(6) 0.0027(5) 0.0014(4) 
C6 0.0044(4) 0.0054(4) 0.0055(7) 0.0025(6) 0.0025(5) 0.0011(4) 
N1' 0.0069(3) 0.0052(3) 0.0069(5) 0.0006(4) 0.0009(4) 0.0005(3) 
C2' 0.0063(5) 0.0056(5) 0.0040(6) 0.0006(5) 0.0009(5) 0.0013(4) 
C3' 0.0079(5) 0.0056(5) 0.0078(7) -0.0001(6) 0.0015(5) 0.0005(4) 
C4' 0.0077(5) 0.0081(5) 0.0071(7) 0.0019(6) 0.0022(5) 0.0019(4) 
C5' 0.0088(6) 0.0097(6) 0.0086(8) 0.0014(7) 0.0036(6) 0.0024(5) 
C6' 0.0074(5) 0.0079(5) 0.0098(8) 0.0009(7) 0.0015(6) 0.0009(4) 
C7' 0.0084(5) 0.0094(6) 0.0095(8) 0.0035(7) 0.0051(6) 0.0012(5) 
H 0.0193(19) 0.0168(17) 0.027(3) 0.008(2) 0.007(2) 0.0044(15) 
H3' 0.023(2) 0.0181(19) 0.028(3) 0.003(2) 0.013(2) -0.0044(16) 
H4' 0.029(3) 0.024(2) 0.019(3) 0.000(3) 0.006(2) 0.006(2) 
H5' 0.025(3) 0.028(3) 0.027(3) 0.011(3) 0.015(3) 0.004(2) 
H6' 0.024(2) 0.0143(17) 0.030(3) -0.001(2) 0.007(2) -0.0042(15) 
H71' 0.047(5) 0.026(3) 0.059(7) 0.014(5) 0.025(5) 0.013(3) 
H72' 0.029(3) 0.043(4) 0.013(2) 0.003(3) 0.009(2) -0.007(3) 
H73' 0.023(3) 0.072(7) 0.045(5) 0.028(6) 0.014(3) 0.024(4) 
 
_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 
O C1 1.319(3) . ? 
O H 1.069(7) . ? 
Cl2 C2 1.717(2) . ? 
Cl3 C3 1.713(2) . ? 
Cl4 C4 1.710(2) . ? 
Cl5 C5 1.720(2) . ? 
Cl6 C6 1.721(2) . ? 
C1 C2 1.405(3) . ? 
C1 C6 1.406(3) . ? 
C2 C3 1.394(3) . ? 
C3 C4 1.396(3) . ? 
C4 C5 1.396(3) . ? 
C5 C6 1.385(3) . ? 
N1' C6' 1.338(4) . ? 
N1' C2' 1.340(3) . ? 
N1' H 1.535(7) . ? 
C2' C3' 1.392(3) . ? 
C2' C7' 1.503(4) . ? 
C3' C4' 1.390(4) . ? 
C3' H3' 1.081(7) . ? 
C4' C5' 1.393(3) . ? 
C4' H4' 1.082(7) . ? 
C5' C6' 1.380(4) . ? 
C5' H5' 1.084(10) . ? 
C6' H6' 1.079(6) . ? 
C7' H71' 1.075(11) . ? 
C7' H72' 1.091(7) . ? 
C7' H73' 1.068(8) . ? 
 
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 
C1 O H 116.9(5) . . ? 
O C1 C2 118.90(18) . . ? 
O C1 C6 123.66(19) . . ? 
C2 C1 C6 117.40(16) . . ? 
C3 C2 C1 121.44(16) . . ? 
C3 C2 Cl2 119.99(15) . . ? 
C1 C2 Cl2 118.56(14) . . ? 
C2 C3 C4 119.90(16) . . ? 
C2 C3 Cl3 119.58(15) . . ? 
C4 C3 Cl3 120.52(15) . . ? 
C3 C4 C5 119.50(16) . . ? 
C3 C4 Cl4 120.20(14) . . ? 
C5 C4 Cl4 120.28(14) . . ? 
C6 C5 C4 120.15(16) . . ? 
C6 C5 Cl5 120.13(15) . . ? 
C4 C5 Cl5 119.72(15) . . ? 
C5 C6 C1 121.60(17) . . ? 
C5 C6 Cl6 120.20(15) . . ? 
C1 C6 Cl6 118.10(15) . . ? 
C6' N1' C2' 119.37(18) . . ? 
C6' N1' H 119.9(3) . . ? 
C2' N1' H 120.3(3) . . ? 
N1' C2' C3' 121.0(2) . . ? 
N1' C2' C7' 117.08(18) . . ? 
C3' C2' C7' 121.9(2) . . ? 
C4' C3' C2' 119.4(2) . . ? 
C4' C3' H3' 121.7(5) . . ? 
C2' C3' H3' 118.8(5) . . ? 
C3' C4' C5' 119.1(2) . . ? 
C3' C4' H4' 120.9(6) . . ? 
C5' C4' H4' 120.0(6) . . ? 
C6' C5' C4' 117.9(3) . . ? 
C6' C5' H5' 121.5(5) . . ? 
C4' C5' H5' 120.6(5) . . ? 
N1' C6' C5' 123.2(2) . . ? 
N1' C6' H6' 115.2(6) . . ? 
C5' C6' H6' 121.5(6) . . ? 
C2' C7' H71' 111.5(7) . . ? 
C2' C7' H72' 111.9(5) . . ? 
H71' C7' H72' 107.6(10) . . ? 
C2' C7' H73' 111.3(8) . . ? 
H71' C7' H73' 105.4(10) . . ? 
H72' C7' H73' 108.9(9) . . ? 
 
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 
O C1 C2 C3 -179.3(3) . . . . ? 
C6 C1 C2 C3 -1.4(4) . . . . ? 
O C1 C2 Cl2 1.7(4) . . . . ? 
C6 C1 C2 Cl2 179.7(2) . . . . ? 
C1 C2 C3 C4 0.6(4) . . . . ? 
Cl2 C2 C3 C4 179.5(2) . . . . ? 
C1 C2 C3 Cl3 179.7(2) . . . . ? 
Cl2 C2 C3 Cl3 -1.4(3) . . . . ? 
C2 C3 C4 C5 0.7(4) . . . . ? 
Cl3 C3 C4 C5 -178.4(2) . . . . ? 
C2 C3 C4 Cl4 179.3(2) . . . . ? 
Cl3 C3 C4 Cl4 0.2(3) . . . . ? 
C3 C4 C5 C6 -1.2(4) . . . . ? 
Cl4 C4 C5 C6 -179.8(2) . . . . ? 
C3 C4 C5 Cl5 179.6(2) . . . . ? 
Cl4 C4 C5 Cl5 1.0(3) . . . . ? 
C4 C5 C6 C1 0.5(4) . . . . ? 
Cl5 C5 C6 C1 179.7(2) . . . . ? 
C4 C5 C6 Cl6 176.7(2) . . . . ? 
Cl5 C5 C6 Cl6 -4.1(4) . . . . ? 
O C1 C6 C5 178.7(3) . . . . ? 
C2 C1 C6 C5 0.8(4) . . . . ? 
O C1 C6 Cl6 2.4(4) . . . . ? 
C2 C1 C6 Cl6 -175.5(2) . . . . ? 
C6' N1' C2' C3' 0.2(3) . . . . ? 
C6' N1' C2' C7' -179.72(19) . . . . ? 
N1' C2' C3' C4' 0.6(3) . . . . ? 
C7' C2' C3' C4' -179.5(2) . . . . ? 
C2' C3' C4' C5' -1.4(3) . . . . ? 
C3' C4' C5' C6' 1.4(3) . . . . ? 
C2' N1' C6' C5' -0.1(3) . . . . ? 
C4' C5' C6' N1' -0.7(3) . . . . ? 
 
_diffrn_measured_fraction_theta_max    0.085 
_diffrn_reflns_theta_full              66.67 
_diffrn_measured_fraction_theta_full   0.085 
_refine_diff_density_max    3.472 
_refine_diff_density_min   -3.094 
_refine_diff_density_rms    0.638