Time-dependent density functional theory scheme for efficient calculations of dynamic (hyper)polarizabilities

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Electronic Structure Theory

Background:

• Accurate calculation of molecular polarizabilities and hyperpolarizabilities is crucial for understanding electronic systems.
• Previous methods often struggle with scalability for large and complex molecules.

Purpose of the Study:

• To develop and validate an efficient perturbative method for static and dynamic polarizabilities and hyperpolarizabilities.
• To enable the study of response properties in very large molecular systems.

Main Methods:

• Utilizes a frequency-dependent Sternheimer equation within time-dependent density functional theory.
• Employs a real-space, basis-set-free implementation for excellent scalability.
• Calculates response properties both in and out of resonance.

Main Results:

• The method demonstrates excellent scaling with the number of atoms.
• Applied to benchmark molecules (CO, H2O, para-nitroaniline), yielding results consistent with experiments and prior theory.
• Fully validates the developed computational approach.

Conclusions:

• The presented method offers an efficient and accurate way to compute polarizabilities and hyperpolarizabilities.
• Its scalability makes it suitable for investigating large molecular systems.
• This work paves the way for advanced studies in molecular electronic properties.