LP correction for Mo

davewragg

Dear All,

I'm currently helping a PhD student to treat some powder data collected on a single crystal instrument. The setup has a graphite monochromator. If I understand correctly the TOPAS LP factor should be the Bragg angle of the Miller plane of the mono under the incident radiation. I worked this through for Ge (111) with copper and came to about 27.3 which is the number in the manual. Using the same working I came to a value of 11.8 for Graphite (002) under moly radiation- does this seem right to those of you who have done something similar (or just know for other reasons)?

I've also suggested that the student uses Ka1 and Ka2 due to the wide bandpass of a graphite mono.

Any thoughts/advice?

Thanks

Dave

mfisch

Didn't check the calc but sounds good. It is always a good idea to check with a standard.

Cheers
Martin