(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2008). E64, m507-m508 [ doi:10.1107/S1600536808005266 ]

Potassium sodium (2R,3R)-tartrate tetrahydrate: the paraelectric phase of Rochelle salt at 105 K

C. H. Görbitz and E. Sagstuen

Online 5 March 2008

Key indicators

Single-crystal X-ray study
T = 105 K
Mean (C-C) = 0.001 Å
R factor = 0.030
wR factor = 0.069
Data-to-parameter ratio = 51.5

checkCIF/PLATON results

No syntax errors found



Alert level A
EXPT108_ALERT_1_A  The magnitudes of the crystal dimensions do not
            match the min, mid and max definitions

Author Response: The crystal was a sphere, only radius given in -exptl-crystal-size-rad 0.5


Alert level B
ABSTM02_ALERT_3_B  The ratio of expected to reported Tmax/Tmin(RR') is < 0.75
            Tmin and Tmax reported:      0.398     0.551
            Tmin(prime) and Tmax expected:      1.000     1.000
            RR(prime) =      0.722
            Please check that your absorption correction is appropriate.

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.79      
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       1.16      
PLAT164_ALERT_4_C Nr. of Refined C-H H-Atoms in Heavy-At Struct...          2      

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      1.816
            Tmax scaled      1.000 Tmin scaled      0.722
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           49.65
           From the CIF: _reflns_number_total              10040
           Count of symmetry unique reflns         5936
           Completeness (_total/calc)            169.14%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      4104
           Fraction of Friedel pairs measured     0.691
           Are heavy atom types Z>Si present        yes
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C2     ...          R      
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C3     ...          R      
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......         12      

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

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   3 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check