Lanczos-driven coupled-cluster damped linear response theory for molecules in polarizable environments

Area of Science:

• Computational chemistry
• Quantum chemistry
• Spectroscopy

Background:

• Coupled-cluster (CC) methods are advanced quantum chemical techniques.
• Modeling molecules in condensed phases requires accounting for environmental effects.
• Polarizable embedding formalism incorporates environmental interactions.

Purpose of the Study:

• Extend Lanczos-driven CC damped linear response for condensed phases.
• Compute core excitations in realistic environments.
• Assess the impact of environmental response on CC excitation calculations.

Main Methods:

• Lanczos-driven coupled-cluster (CC) damped linear response.
• Polarizable embedding formalism for condensed phase environments.
• Investigation of the CC J matrix contribution to excitation energies.

Main Results:

• Environmental polarization effects from CC multipliers (J matrix) are minor for solvatochromic shifts.
• Numerical validation of neglecting the J matrix contribution in excitation energy calculations.
• Environment significantly influences transition-specific shifts.

Conclusions:

• The approximation of neglecting the J matrix contribution is numerically validated.
• This approximation reduces computational cost and problem dimensionality.
• Future studies can benefit from this validated approximation for condensed-phase calculations.