(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2012). E68, o2084
[ doi:10.1107/S1600536812025196 ]

2-Amino-5-methylpyridinium nitrate

X. Yan, Y. Fan, C. Bi, J. Zuo and Z. Zhang

Key indicators

Single-crystal X-ray study
T = 298 K
Mean (C-C) = 0.004 Å
R factor = 0.039
wR factor = 0.109
Data-to-parameter ratio = 11.3

checkCIF/PLATON results

No syntax errors found




Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N3     
PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds ...............     0.0042 Ang  
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.595          3      
PLAT915_ALERT_3_C Low Friedel Pair Coverage ......................         70 Perc.

Alert level G
REFLT03_ALERT_4_G  ALERT: MoKa measured Friedel data cannot be used to
                   determine absolute structure in a light-atom
                   study EXCEPT under VERY special conditions.
                   It is preferred that Friedel data is merged in such cases.
           From the CIF: _diffrn_reflns_theta_max           25.01
           From the CIF: _reflns_number_total               1251
           Count of symmetry unique reflns          742
           Completeness (_total/calc)            168.60%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       509
           Fraction of Friedel pairs measured     0.686
           Are heavy atom types Z>Si present         no
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT007_ALERT_5_G Note: Number of Unrefined D-H Atoms ............          3      
PLAT909_ALERT_3_G Percentage of Observed Data at Theta(Max) still          62 Perc.

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   4 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   2 ALERT type 5 Informative message, check