john201004
I know I have mixture of hydrogen and deuterium in my unit cell. So I define it as
site D1 x = 0; y = 0; z = 0; occ D-1 =1-H_content; beq ThemalH 0.4
site H1 x = 0; y = 0; z = 0; occ H-1 !H_content 0.2 beq ThemalH 0.4
However, I am not really sure to use the same beq values for both atoms? As temperature factor defined as:
M=8*pi^2<u^2>(sin^2 theta)/lambda^2
and <u^2> is the mean square displacement amplitude. I thought it is correct to use same values for both hydrogen and deuterium but I am not entirely sure. Please help me to clarify this?
johnsoevans
If you have two atoms on the same site you really have no sensible choice apart from equating their temperature factors.
john201004
Does above expression correct for express a mixture of atoms in the unit cell?
or should I create two different phases for two different atoms?
or there is any other alternatives?
Sincerely
johnsoevans
John: This is not meant to be a rude response, but you must read a crystallography text book if you have this type of question. If you're unsure on this it's very likely that you'll make significant errors elsewhere in your work.
john201004
Could you please suggest me any good text books?