(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2009). E65, o538 [ doi:10.1107/S1600536809005005 ]

Bis[4-(2-benzylidenepropylideneamino)phenyl] ether

M. Movahedi, H. Hadadzadeh, K. Fejfarova, M. Dusek and A. Dehno Khalaji

Online 18 February 2009

Key indicators

Single-crystal X-ray study
T = 295 K
Mean (C-C) = 0.003 Å
R factor = 0.036
wR factor = 0.120
Data-to-parameter ratio = 12.1

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT027_ALERT_3_A _diffrn_reflns_theta_full (too) Low ............      61.20 Deg.

Author Response: see PLAT023


Alert level B
THETM01_ALERT_3_B  The value of sine(theta_max)/wavelength is less than 0.575
            Calculated sin(theta_max)/wavelength =    0.5694

Author Response: see PLAT023


PLAT023_ALERT_3_B Resolution (too) Low [sin(theta)/Lambda < 0.6]..      61.40 Deg.

Author Response: The diffractometer Gemini used for the data collection has two X-ray tubes, Mo and Cu. The collimator of Mo tube limits the maximal theta angle of CCD detector and the required resolution cannot be easily achieved with Cu radiation. In order to achieve resolution 0.83 instead of 0.89 almost 2000 frames would be added to the experiment or we would need to measure with removed Mo collimator; the first way is not efficient, the second one is laborius ans unsafe. Because the required resolution is not very far of the one actually reached we are using the normal data collection mode.


Alert level C
            Value of measurement temperature given =   295.000
            Value of melting point given =     0.000
GOODF01_ALERT_2_C  The least squares goodness of fit parameter lies
            outside the range 0.80 <> 2.00
            Goodness of fit given =      2.320

Author Response: see PLAT087

PLAT087_ALERT_2_C Unsatisfactory S value (Too High) ..............       2.32

Author Response: Program Jana has a different weighting scheme of SHELX, see _refine_special_details, and th eresulting g.o.f is usually higher compared with SHELX. Another reason for higher g.o.f. was high exposition time used for data collection of this compound and merohedric twinning with non-equal twin fractions.



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

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