Journal Article 4 focal point analysis 2 18-crown-6 1 Research Support, Non-U.S. Gov't 1 ammonium cation 1 basis set extrapolation 1 crown ether 1 mehr ... density functional theory 1 focal-point analysis 1 focal-point analysis of interaction energies 1 halogen substitution 1 interconversion rate coefficients 1 ion-aromatic-ring interaction 1 laser-induced alignment 1 laser-induced orientation 1 molecular properties 1 n-alkanes 1 natural bond orbital analysis 1 non-covalent interaction 1 perturbation theory 1 thermochemistry 1 uncertainty analysis 1 weniger ...