Continuous and smooth potential energy surface for conductorlike screening solvation model using fixed points with...

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Theoretical Chemistry

Background:

• Accurate potential energy surfaces and analytic gradients are crucial for reliable molecular geometry optimizations.
• Continuity and smoothness of these surfaces are essential for stable and efficient computational chemistry methods.
• Existing solvation models may face challenges in providing these properties, impacting optimization convergence.

Purpose of the Study:

• To develop and implement a novel tessellation scheme, fixed points with variable areas (FIXPVA), for the conductorlike screening model (CPCM).
• To obtain rigorously continuous and smooth potential energy surfaces and exact analytic gradients for CPCM.
• To enable stable and convergent geometry optimizations using various quantum chemical methods.

Main Methods:

• Implementation of the FIXPVA tessellation scheme for defining the molecular cavity in CPCM.
• Calculation of analytic derivatives of surface tesserae positions and areas with respect to atomic coordinates.
• Application of the method with Hartree-Fock (HF) and density functional theory (DFT) approaches, including restricted (R), unrestricted (U), and restricted open-shell (RO) variants.

Main Results:

• The FIXPVA scheme successfully generates continuous and smooth potential energy surfaces for CPCM.
• Exact analytic gradients for solvation energy are accurately computed.
• Geometry optimizations demonstrate stable and convergent behavior across HF and DFT methods.

Conclusions:

• The FIXPVA tessellation scheme offers a robust approach for accurate and efficient solvation modeling.
• The obtained analytic gradients and smooth potential energy surfaces significantly improve the reliability of geometry optimizations.
• This method enhances the applicability of CPCM in computational chemistry studies.