[RMCProfile-users] Huge Chi2 with the initial run

[Ramanathan, Arun]

Hello,
     I have synchrotron PDF data. F(Q) was obtained by calibrating using GSAS II. The initial run with a weight of 0.01 for the X-ray reciprocal block seems to give me a huge Chi2 (0.1222E+5). This doesn't seem reasonable. I was wondering if you might be able with this. Here is the .dat file I am using -


TITLE :: Na2SnO3
MATERIAL :: Na2SnO3
PHASE :: C2c
TEMPERATURE :: RT
PRESSURE :: RP
DATA_NOTE :: First
RMC_NOTE :: tutorial example: not necessarily the best fit!
INVESTIGATOR :: Arun

NUMBER_DENSITY ::   0.070712 Angstrom^(-3)
MAXIMUM_MOVES ::   0.02  0.02  0.02 Angstrom
R_SPACING ::  0.0200 Angstrom
PRINT_PERIOD :: 1000
TIME_LIMIT ::  0.0 MINUTES
SAVE_PERIOD :: 0.0  MINUTES


ATOMS :: Na Sn O


FIXED_COORDINATION_CONSTRAINTS :: 2
  > CSTR1 :: 1 3 1.9 2.9 6 1.0 0.00001
  > CSTR2 :: 2 3 1.9 2.6 6 1.0 0.00001

DISTANCE_WINDOW ::
  > MNDIST :: 3.1 3.1 1.9 3.3 1.9 2.8
  > MXDIST :: 4.0 4.0 2.8 4.0 2.5 4.0

INPUT_CONFIGURATION_FORMAT ::  rmc6f
SAVE_CONFIGURATION_FORMAT  ::  rmc6f


IGNORE_HISTORY_FILE ::

FLAGS ::
  > NO_MOVEOUT
  > NO_SAVE_CONFIGURATIONS
  > NO_RESOLUTION_CONVOLUTION

XRAY_RECIPROCAL_SPACE_DATA ::
  > FILENAME :: Na2PrO3.fq
  > DATA_TYPE :: F(Q)
  > FIT_TYPE :: F(Q)
  > CONVOLVE ::
  > FITTED_SCALE
  > RECIPROCAL_SPACE_FIT :: 100 2850 1
  > RECIPROCAL_SPACE_PARAMETERS :: 100 2850 0.01


END ::

Cheers
Arun

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