Response Properties at the SCF Level

Therefore, the term involved in the energy gradient simplifies to 

In this way the final density matrix-based energy gradient expression results, which avoids the use of the conventional energy-weighted density matrix (which is conventionally constructed via the delocalized, canonical MO coefficients)  

With the energy gradients at hand, one can now locate stationary points on a potential hypersurface or study the dynamics of a system. However, a huge class of important molecular properties is more complicated to calculate. 

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