# Instantaneous normal modes in liquids: a heterogeneous-elastic-medium approach

@inproceedings{Mossa2023InstantaneousNM, title={Instantaneous normal modes in liquids: a heterogeneous-elastic-medium approach}, author={Stefano Mossa and Taras Bryk and Giancarlo Ruocco and Walter Schirmacher}, year={2023} }

The concept of vibrational density of states in glasses has been mirrored in liquids by the instantaneous-normal-mode spectrum. While in glasses instantaneous configurations correspond to minima of the potential-energy hypersurface and all eigenvalues of the associated Hessian matrix are therefore positive, in liquids this is no longer true, and modes corresponding to both positive and negative eigenvalues exist. The instantaneous-normal-mode spectrum has been numerically investigated in the…

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