Predicting structure of molecular crystals from first principles.

Area of Science:

• Computational chemistry
• Materials science
• Crystallography

Background:

• Predicting molecular crystal structures from first principles is crucial for understanding material properties.
• Accurate and efficient computational methods are needed for crystal structure prediction.

Purpose of the Study:

• To evaluate the accuracy and efficiency of symmetry-adapted perturbation theory based on the density-functional description of monomers (SAPT(DFT)) for molecular crystal structure prediction.
• To demonstrate the utility of SAPT(DFT) in predicting crystal polymorphs and lattice energies.

Main Methods:

• Symmetry-adapted perturbation theory based on the density-functional description of monomers (SAPT(DFT)) was employed.
• The method was applied to predict the crystal structure and polymorphs of cyclotrimethylene trinitramine.
• Lattice energy calculations were performed for the benzene crystal.

Main Results:

• The SAPT(DFT) potential accurately generated and ordered polymorphs of cyclotrimethylene trinitramine, with the lowest-energy structure matching experimental data.
• SAPT(DFT) calculations reproduced the lattice energy of the benzene crystal with high accuracy (within a few percent).

Conclusions:

• SAPT(DFT) is a sufficiently accurate and numerically efficient method for first-principles prediction of molecular crystal structures.
• This method shows significant promise for applications in materials science and drug discovery.