TY - JOUR

T1 - Ortho-para nuclear-spin isomerization energies for all bound vibrational states of ditritium (T2) from non-Born-Oppenheimer variational calculations performed with explicitly correlated all-particle Gaussian functions

AU - Kirnosov, Nikita

AU - Sharkey, Keeper L.

AU - Adamowicz, Ludwik

N1 - Funding Information:
This work has been supported in part by the National Science Foundation through the graduate research fellowship program (GRFP) awarded to Keeper L. Sharkey; grant number DGE1-1143953 . It has been also supported in part by the National Science Foundation with grant number IIA-1444127 . We are grateful to the University of Arizona Center of Computing and Information Technology for the use of their computer resources. This work has been also supported in part by the National Science Foundation with grant #IIA-1444127 .

PY - 2015/11/1

Y1 - 2015/11/1

N2 - Graphical Direct variational calculations, where the Born-Oppenheimer (BO) approximation is not assumed, are performed for all 26 bound rovibrational states corresponding to the lowest rotational excitation (i.e. the N = 1 states) of the tritium molecule (T2). The non-BO energies are used to determine the ortho-para isomerization energies. All-particle explicitly correlated Gaussian basis functions are employed in the calculations and over 11 000 Gaussians independently generated for each state are used. The exponential parameters of the Gaussians are optimized with the aid of analytically calculated energy gradient determined with respect to these parameters. The non-BO wave functions are used to calculate expectation values of the inter-particle distances and the triton-triton correlation functions.

AB - Graphical Direct variational calculations, where the Born-Oppenheimer (BO) approximation is not assumed, are performed for all 26 bound rovibrational states corresponding to the lowest rotational excitation (i.e. the N = 1 states) of the tritium molecule (T2). The non-BO energies are used to determine the ortho-para isomerization energies. All-particle explicitly correlated Gaussian basis functions are employed in the calculations and over 11 000 Gaussians independently generated for each state are used. The exponential parameters of the Gaussians are optimized with the aid of analytically calculated energy gradient determined with respect to these parameters. The non-BO wave functions are used to calculate expectation values of the inter-particle distances and the triton-triton correlation functions.

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U2 - 10.1016/j.cplett.2015.10.017

DO - 10.1016/j.cplett.2015.10.017

M3 - Article

AN - SCOPUS:84944875668

VL - 640

SP - 61

EP - 67

JO - Chemical Physics Letters

JF - Chemical Physics Letters

SN - 0009-2614

ER -