Hello all.

Does anyone know if kinetic energy in DMol3 has a real meaning? I have never payed attention to it, but recently noticed it is negative. I checked different (fully relaxed) systems: molecules, metals. Kinetic energy was negative even for Hydrogen atom.

Is total/binding energy the only usable parameter? What is DMol kinetic energy?

Thanks.

P.S.The manual defines kinetic energy as a sum of matrix elements \\Psi \\grad^2 \\Psi, where \\Psi are the Kohn-Sham orbitals.