<i>Ab initio</i>molecular dynamics for liquid metals
Georg Kresse, J. Häfner
Abstract
We present ab initio quantum-mechanical molecular-dynamics calculations based on the calculation of the electronic ground state and of the Hellmann-Feynman forces in the local-density approximation at each molecular-dynamics step. This is possible using conjugate-gradient techniques for energy minimization, and predicting the wave functions for new ionic positions using subspace alignment. This approach avoids the instabilities inherent in quantum-mechanical molecular-dynamics calculations for metals based on the use of a fictitious Newtonian dynamics for the electronic degrees of freedom. This method gives perfect control of the adiabaticity and allows us to perform simulations over several picoseconds.
Topics & Concepts
Degrees of freedom (physics and chemistry)Molecular dynamicsAb initioPhysicsQuantumElectronic structureQuantum dynamicsGround stateAb initio quantum chemistry methodsWave functionPicosecondPotential energyClassical mechanicsQuantum mechanicsMoleculeLaserHigh-pressure geophysics and materialsSpectroscopy and Quantum Chemical StudiesQuantum, superfluid, helium dynamics