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The higher-order C_n dispersion coefficients for hydrogen

J. Mitroy·M. W. J. Bromley
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Abstract

The complete set of 2nd, 3rd and 4th order van der Waals coefficients, C_n up to n=32 for the H(1s)-H(1s) dimer are computed using pseudo-states to evaluate the appropriate sum rules. A study of the convergence pattern for n<=16 indicates that all the C_n (n<=16) coefficients are accurate to 13 significant digits. The relative size of the 4th-order C^4_n to the 2nd-order C^2_n coefficients is seen to increase as n increases and at n=32 the 4th-order term is actually larger.

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J. Mitroy, M. W. J. Bromley. 2004-11-19. The higher-order C_n dispersion coefficients for hydrogen. https://doi.org/10.1103/physreva.71.032709

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