Artemis/Ifeffit allow both the third and fourth cumulants to be fitting parameters. Assigning a guess parameter to the third cumulant, particularly for near neighbor paths, can sometimes be quite useful. A fit that requires cumulants beyond the fourth is usually so disordered that a cumulant expansion isn't the best strategy anyway.

On Dec 26, 2007, at 6:12 PM, Luanga Nchari wrote:

Merry Christmas to all. I am a research student with the following questions:
· Does Artemis have a cumulant expansion feature?
How can it be used to correct anharmonicity?
I suspect this might answer why my fit in K-space is not quite in phase eventhough the fit in R-space is good.
Other suggestions would be welcome.
Thanks,
Luanga Nchari

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