Dear all,

Hope you have a good day.

Whether it's rare or not, when it comes to calculating the DFT with the spin unristricted option, it takes the risk of "spin contamination".

The only way I know how to determine the system suffers the spin contamination is to compare the theoretical eigenvalue of the total spin and that of the calculated value.

However, when I calculated the spin in the CASTEP and DMol3, which the most popular quantum mechanics modules in the Materials Studio, they don't seem to printed out the spin eigenvalue.

In this case, how can I determine the system includes the spin contamination or not?

BTW, I figured out the TURBOMOLE printed out the S^2 value.

Thank you.

Best regards,

Rakhoon Choi