(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2004). E60, o1491-o1493 [ doi:10.1107/S1600536804018793 ]

3-Ammonio-2,6-dibromopyridine bromide hemihydrate

S. F. Haddad, M. A. AlDamen and R. H. Al-Far

Online 7 August 2004

Key indicators

Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.009 Å
R factor = 0.032
wR factor = 0.079
Data-to-parameter ratio = 21.6

checkCIF/PLATON results

No syntax errors found




Alert level B
PLAT431_ALERT_2_B Short Inter HL..A Contact  Br4    ..  Br5     ..       3.36 Ang.  

Alert level C
PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings    Differ ....          ?
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT045_ALERT_1_C Calculated and Reported Z Differ by ............       0.50 Ratio 
PLAT341_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          9       
PLAT417_ALERT_2_C Short Inter D-H..H-D       H1'    ..  H2B     ..       2.13 Ang.  
PLAT431_ALERT_2_C Short Inter HL..A Contact  Br1    ..  Br4     ..       3.44 Ang.  
PLAT480_ALERT_4_C Long H...A H-Bond Reported H2C    ..  BR4     ..       3.01 Ang.  
PLAT480_ALERT_4_C Long H...A H-Bond Reported H2     ..  N1      ..       2.87 Ang.  
PLAT481_ALERT_4_C Long D...A H-Bond Reported C2     ..  N1      ..       3.80 Ang.  

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.86
           From the CIF: _reflns_number_total               2189
           Count of symmetry unique reflns         1193
           Completeness (_total/calc)            183.49%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       996
           Fraction of Friedel pairs measured     0.835
           Are heavy atom types Z>Si present          yes

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   9 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion