Geometric constraints in semiclassical initial value representation calculations in Cartesian coordinates: excited...

Area of Science:

• Quantum Chemistry
• Computational Physics

Background:

• Semiclassical initial value representation (SC-IVR) calculations are a powerful tool for molecular simulations.
• Accurately determining excited states of weakly bound complexes remains a challenge.
• Geometric constraints can refine computational models but their integration into SC-IVR is complex.

Purpose of the Study:

• To adapt and validate a recently proposed method for incorporating geometric constraints into SC-IVR calculations.
• To assess the method's capability in calculating excited states of weakly bound systems.
• To compare the accuracy of the constrained SC-IVR approach with exact methods.

Main Methods:

• The study applies a novel approach for geometric constraint inclusion within SC-IVR.
• Sample calculations were performed on free and constrained rare gas clusters.
• Results were benchmarked against exact basis set calculations.

Main Results:

• The proposed method successfully obtains excited states for weakly bound complexes.
• Calculations on rare gas clusters demonstrated the approach's effectiveness.
• The constrained SC-IVR method yielded results with reasonable accuracy compared to exact calculations.

Conclusions:

• The adapted SC-IVR method with geometric constraints is a viable approach for calculating excited states.
• This technique provides accurate results for weakly bound complexes.
• The study validates the utility of incorporating geometric constraints in semiclassical calculations for complex systems.