Accurate thermochemistry of covalent and ionic solids from spin-component-scaled MP2

Area of Science:

• Computational quantum chemistry
• Materials science
• Solid-state physics

Background:

• Accurate prediction of material properties is crucial for discovering new semiconductors and insulators.
• Second-order Møller-Plesset perturbation theory (MP2) provides good accuracy but can be computationally expensive.
• Density functional theory (DFT) methods often struggle with quantitative accuracy for certain material properties.

Purpose of the Study:

• To evaluate the performance of spin-component-scaled second-order Møller-Plesset perturbation theory (SCS-MP2) for predicting key properties of solids.
• To compare SCS-MP2 and scaled opposite-spin MP2 (SOS-MP2) with MP2 and leading density functionals.
• To investigate the transferability of SCS-MP2 parameters for solid-state applications.

Main Methods:

• Calculations were performed for 12 simple, three-dimensional covalent and ionic semiconductors and insulators.
• Spin-component-scaled second-order Møller-Plesset perturbation theory (SCS-MP2) and scaled opposite-spin MP2 (SOS-MP2) were employed.
• Results were compared to experimental data, including zero-point vibrational corrections.

Main Results:

• SCS-MP2 and SOS-MP2 significantly improve upon MP2 predictions for lattice constants, bulk moduli, and cohesive energies.
• Mean absolute errors for SCS-MP2 were 0.015 Å (lattice constant), 3.8 GPa (bulk modulus), and 0.06 eV (cohesive energy).
• These errors are approximately half those of leading density functionals, demonstrating superior accuracy.

Conclusions:

• SCS-MP2 and SOS-MP2 are highly accurate methods for predicting the properties of semiconductors and insulators.
• The optimal spin-scaling parameters are transferable from molecular chemistry to solid-state applications.
• These methods show promise for future studies in surface chemistry on insulators.