Energy levels and wave functions of weakly-bound 4Hex 20NeyH (x+y=2) systems using Pekeris coordinates and a symmetry-adapted Lanczos approach.

Energy levels and wave functions of floppy triatomic rare gas hydrides are calculated using a Pekeris coordinate system and the importance of various triangular configurations is assessed through the calculation of reduced distribution functions and relative weights. The calculations are performed using a symmetry-adapted Lanczos recursion within the discrete variable representation. For the 4He2H- anion, the present results are compared with those obtained from calculations based on other methods, and the accuracy of the present method is discussed. Calculations are also performed for the case of 4He2H and 20Ne2H, as well as for the mixed 4He 20NeH neutrals. Our results show that no bound states are found for 4He2H while only one bound state is found for both the 20Ne2H and 4He 20NeH complexes. Interestingly, a very important and common property of these systems is that there is a significant contribution from linear configurations to their bound states.

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