Intermolecular interactions in molecular crystals and glasses

NQR Studies of Phase Transitions and Intermolecular Interactions in Crystals*

Simple methods to analyze the anomalous behavior o f NQ R parameters are presented. Unusual positive temperature coefficients o f antimony resonance frequencies in (N H 4)2SbF5 below the phase transition at 169 K were interpreted in terms o f ordering processes o f the ammonium ions. Calculation o f the EFG in LaF3 revealed that the translational diffusion of Li ions brings about an anomalous d...

Accurate and Efficient Model Energies for Exploring Intermolecular Interactions in Molecular Crystals.

The energy of interaction between molecules is commonly expressed in terms of four key components: electrostatic, polarization, dispersion, and exchange-repulsion. Using monomer wave functions to obtain accurate estimates of electrostatic, polarization, and repulsion energies along with Grimme's dispersion corrections, a series of energy models are derived by fitting to dispersion-corrected DFT...

Intermolecular Interaction Energies in Molecular Crystals of 4-Formylcoumarin Derivatives

Most of the crystallographic analysis that follows from structure determination involves interpretation of the molecular geometry and a working knowledge of a variety of intraand intermolecular interactions based purely on geometrical considerations (distance and angle cut off criteria). The missing link is to explore the energetics associated with these interactions, particularly intermolecula...

First-principles intermolecular binding energies in organic molecular crystals

The intermolecular binding (lattice) energies are calculated for the molecular crystals cyclotrimethylene trinitramine, pentaerythritol, and pentaerythritol tetranitrate using the CRYSTAL 98/03 and GAUSSIAN 98 programs, the DMOL program and the CASTEP program and compared with experiment. Calculating the theoretical intermolecular binding energy as a tool for testing the intrinsic quality of a ...

Exciton–Phonon Interactions in Molecular Crystals