(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2007). E63, o4032 [ doi:10.1107/S1600536807043747 ]

1-Hydroxycyclobutane-1-carboxylic acid

R. Betz and P. Klüfers

Key indicators

Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.004 Å
R factor = 0.029
wR factor = 0.079
Data-to-parameter ratio = 8.0

checkCIF/PLATON results

No syntax errors found




Alert level C
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         C4

Author Response: correct assignment of element type, atom shows comparatively higher degree of conformational flexibility than neighbouring atoms, splitting not indicated. cf comment item for a comparable example apparent in the literature.


Alert level G
REFLT03_ALERT_1_G ALERT: Expected hkl max differ from CIF values
           From the CIF: _diffrn_reflns_theta_max           27.48
           From the CIF: _reflns_number_total                659
           From the CIF: _diffrn_reflns_limit_ max hkl   13.   10.   37.
           From the CIF: _diffrn_reflns_limit_ min hkl  -13.  -10.  -37.
           TEST1: Expected hkl limits for theta max
           Calculated maximum hkl   13.   13.   37.
           Calculated minimum hkl  -13.  -13.  -37.
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           27.48
           From the CIF: _reflns_number_total                659
           Count of symmetry unique reflns          663
           Completeness (_total/calc)             99.40%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K    
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K    
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1      

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

   3 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
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check