Path integral molecular dynamics (PIMD) simulations at the zero thermal temperature still remain inconceivable. Herein, the quantum-mechanical partition function is revised in conjunction with the time independent Schrodinger equation. The imaginary temperature for the quantum mechanical partition function is introduced as an independent variable and defined under the guidance of the virial theorem. In the end, computational evidences are provided showing that this revised PIMD simulation at the zero thermal temperature reproduces both the zero-point energy and the probability density obtained from the Schrodinger equation for the harmonic oscillator. (C) 2017 Elsevier B.V. All rights reserved.