How to calculate thermionic work function

[nuby]

How do you calculate the thermionic work function of an element (hydrogen for example)?

I understand it is usually about 1/2 the ionization energy , but is there a formula to get the exact energy?

Can hydrogen even have a work function?

Thanks in advance.

 

[dipstik]

its related to the fermi energy more than the ionization energy, but the difficult part is the effective surface dipole

try this:

DOI: 10.1103/PhysRevB.68.195408

 

[nuby]

Thanks. Do you have a link for it?