(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2006). E62, o882-o884 [ doi:10.1107/S1600536806003606 ]

L-Tyrosine n-butyl ester

S.-S. Qian, H.-L. Zhu and E. R. T. Tiekink

Online 3 February 2006

Key indicators

Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.005 Å
R factor = 0.050
wR factor = 0.133
Data-to-parameter ratio = 8.7

checkCIF/PLATON results

No syntax errors found




Alert level B
PLAT024_ALERT_4_B Merging of Friedel Pairs is STRONGLY Indicated .          !

Alert level C
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K     
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K     
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C10    -   C11     ..       5.61 su    
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          5       

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           25.00
           From the CIF: _reflns_number_total               2253
           Count of symmetry unique reflns         1341
           Completeness (_total/calc)            168.01%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       912
           Fraction of Friedel pairs measured     0.680
           Are heavy atom types Z>Si present         no

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

   2 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
   1 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion