Related Experiment Video
Updated: Jun 14, 2026

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Results and perspectives of the MO-VB method. Application examples on the He2 and the LiH-He complexes
Fausto Cargnoni1, Mario Raimondi
1CNR-ISTM, Via Golgi 19, 20133 Milano, Italy. f.cargnoni@istm.cnr.it
Abstract:
We present a short overview and two benchmark applications of the Molecular Orbital-Valence Bond (MO-VB) method, a quantum mechanical scheme developed within the framework of modern Valence Bond theory. The MO-VB has been especially designed to deal with weak intermolecular interactions, and in recent years it has been successfully applied to compute the potential energy surface of several complexes, namely He(2), He-H(2)O, He-CH(4) and Ne-CH(4). In this investigation we test extensively the performance of the MO-VB on two limit systems, the He dimer and the LiH-He complex, which span three extremes in the field of van der Waals interactions: a purely dispersive system (He...He) and, thanks to the highly polar Li-H bond, a noble gas approaching a cation (He...Li(+)), and an anion (He...H(-)). Very accurate computations are available in the literature for He(2) and LiH-He, performed either with conventional Molecular Orbital or Monte Carlo approaches, and hence these systems are the ideal candidates to establish the capabilities of the MO-VB. Based on the results of our study, we conclude that in He(2) and LiH-He the MO-VB overestimates the correlation energy contribution to the interaction energy of about 5%, and hence it is a valid option for computing accurate lower bounds to the potential energy surface of these complexes.
More Related Videos
07:14Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
08:54Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
Published on: January 25, 2020
Related Concept Videos
Valence Bond Theory
Molecular Orbital Theory II
¹H NMR: Complex Splitting
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Hybridization of Atomic Orbitals I
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
MO Theory and Covalent Bonding