Molecular magnets properties

In the Hamiltonian conventionally used for derivations of molecular magnetic properties, the applied fields are represented by electromagnetic vector and scalar potentials [1,20] and if desired, canonical transformations are invoked to change the magnetic gauge origin and/or to introduce electric and magnetic fields explicitly into the Hamiltonian, see e.g. refs. [1,20,21]. Here we take as our point of departure the multipolar Hamiltonian derived in ref. [22] without recourse to vector and scalar potentials. 

Ciofini, I. and Daul, C. A. 2003. DFT Calculations of Molecular Magnetic Properties of Coordination Compounds , Coord. Chem. Rev.. 238, 187. 

Effects of a Static Electric Field on Molecular Magnetic Properties Employing the CTOCD Method Shielding Polarizabilities of CO, H20, and CH4 Compounds... 

Molecular Magnetic Properties in the Presence of a Static Electric Field. 

We shall briefly review some definitions to compute molecular magnetic properties in the presence of a static electric field, L e., hypermagnetizabilities and shielding polarizabilities, Zafr and a1. ... 

The ACID ATj can be plotted as an isosurface similar to the total electron density. However, in contrast to the total electron density, only nonlocal (delocalized) electrons contribute to AT, . For a more detailed analysis of molecular magnetic properties, the current density vectors can be plotted onto the ACID hypersurface. It is important to note that the ACID, as defined earlier, is invariant with respect to the relative orientation of the molecule and the magnetic field. Therefore, the ACID hypersurface is unambiguous even in nonplanar and unsymmetric systems. 

The central aim of this chapter is to give a simple, self-contained approach to a set of molecular magnetic properties in terms of induced current densities and related property density maps, via classical relationships combined with quantum mechanical definitions, and computational procedures. Some efforts are made to document the effectiveness of such a theoretical treatment, in the attempt to rationalize the phenomenology and to form a mental image of the mechanisms underlying the electronic interaction with static magnetic perturbations. 

Lazzeretti, P., Malagoli, M., and Zanasi, R. (1994). Computational approach to molecular magnetic properties by continuous transformation of the origin of the current density. Chem. Phys. Lett, 220, 299-304. 

Lazzeretti, P., 8c Zanasi, R. (1996). Molecular magnetic properties via formal annihilation of paramagnetic contribution to electronic current density. International Journal of Quantum Chemistry, 60, 249. 

Circular Dichroism Vibrational Configuration Interaction Configuration Interaction PCI-X and Applications Density Functional Theory (DFT), Hartree-Fock (HF), and the Self-consistent Field Magnetic Circular Dichroism of n Systems Molecular Magnetic Properties Nucleic Acid Conformation and Flexibility Modeling Using Molecular Mechanics Spectroscopy Computational Methods Stereochemistry Representation and Manipulation. 

Benchmark Studies on Small Molecules Configuration Interaction Gradient Theory Green s Functions and Propagators for Chemistry Molecular Magnetic Properties Mpl-ler-Plesset Perturbation Theory ru-Dependent Wavefunc-tions Spin Contamination. 

Atoms in Molecules Electrostatic Potentials Chemical Applications Localized MO SCF Methods Molecular Magnetic Properties Natural Bond Orbital Methods Natural Orbitals Population Analyses for Semiempirical Methods Shape Analysis. 

Integrals of Electron Repulsion Molecular Magnetic Properties Mpller-Plesset Perturbation Theory NMR Chemical Shift Computation Ab Initio Nonadiabatic Derivative Couplings Normal Modes Reaction Path Following Spectroscopy Computational Methods Time-dependent Multi-configurational Hartree Method Transition Structure Optimization Techniques. 

At any rate, in the last 20 years, the main concern of quantum chemists studying molecular magnetic properties has been that of developing approximate computational schemes that ensure invariance of theoretical results in a gauge translation, namely the IGLO, LORG, and GIAO methods (see, e.g., Pulay et al. ). 

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