# Eckart ro-vibrational Hamiltonians via the gateway Hamilton operator: Theory and practice.

@article{Szalay2017EckartRH, title={Eckart ro-vibrational Hamiltonians via the gateway Hamilton operator: Theory and practice.}, author={Viktor Szalay}, journal={The Journal of chemical physics}, year={2017}, volume={146 12}, pages={ 124107 } }

Recently, a general expression for Eckart-frame Hamilton operators has been obtained by the gateway Hamiltonian method [V. Szalay, J. Chem. Phys. 142, 174107 (2015) and V. Szalay, J. Chem. Phys. 143, 064104 (2015)]. The kinetic energy operator in this general Hamiltonian is nearly identical to that of the Eckart-Watson operator even when curvilinear vibrational coordinates are employed. Its different realizations correspond to different methods of calculating Eckart displacements. There are at…

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