What is the reason of getting negative value of thermal parameter in Rietveld refinment ?

03 March 2018 1 980 Report

Since, thermal parameter expression is having square term of atomic displacement, what program does so that we get negative value (nonphysical meaning) of thermal parameter or what can happen with the atomic vibration ?

Dinesh Kumar

Follow the discussions on the following question:

https://www.researchgate.net/post/Is_it_possible_to_have_a_negative_thermal_isotropy_factor

https://www.researchgate.net/post/Why_is_overall_B_factor_negative_in_my_refinement_using_Fullprof

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