(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2003). E59, o1488-o1489 [ doi:10.1107/S160053680301986X ]

1,3-Dibenzylthymine

J.-C. Ding, M.-C. Liu, H.-P. Xiao and M.-L. Hu

Online 18 September 2003

Key indicators

Single-crystal X-ray study
T = 273 K
Mean (C-C) = 0.003 Å
R factor = 0.039
wR factor = 0.098
Data-to-parameter ratio = 16.7

checkCIF/PLATON results

No syntax errors found






Alert level C
PLAT024_ALERT_4_C Merging of Friedel Data Preferred for Z<=Si ....          !
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C9     -   C11      =       5.25 su    
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C17    -   C18      =       6.81 su    
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C18    -   C19      =       5.56 su    
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....         C4     
PLAT331_ALERT_2_C Small Av. Phenyl C-C Dist. C1     -   C6       =       1.37 Ang.  

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           27.02
           From the CIF: _reflns_number_total               3508
           Count of symmetry unique reflns         2030
           Completeness (_total/calc)            172.81%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1478
           Fraction of Friedel pairs measured     0.728
           Are heavy atom types Z>Si present           no

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

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