Magnetism in graphene nanoislands

We study the magnetic properties of nanometer-sized graphene structures with triangular and hexagonal shapes terminated by zigzag edges. We discuss how the shape of the island, the imbalance in the number of atoms belonging to the two graphene sublattices, the existence of zero-energy states, and the total and local magnetic moment are intimately related. We consider electronic interactions both in a mean-field approximation of the one-orbital Hubbard model and with density functional calculations. Both descriptions yield values for the ground state total spin S consistent with Lieb’s theorem for bipartite lattices. Triangles have a finite S for all sizes whereas hexagons have S=0 and develop local moments above a critical size of ≈1.5  nm.

Magnetism and photophysics in supramolecular transition-metal compounds

Based on a synthetic strategy, extended anionic, homo and bimetallic oxalato-bridged transition-metal compounds with two (2D) and three-dimensional (3D) connectivities can be synthesized and crystallized. Thereby, the choice of the templating counterions will determine the crystal chemistry. Since the oxalato bridge is a mediator for both antiferro and ferromagnetic interactions between similar and dissimilar metal ions, long-range magnetic ordering will occur. Examples of the determination of magnetic structures in 2D and 3D compounds by means of elastic neutron scattering methods will be discussed. In addition, due to the possibility of the variation of different metal ions in varying oxidation states, interesting photophysical processes can be observed within the extended three-dimensional host/guest systems.

Rock magnetism of pelagic sediments from DSDP Leg 85 sites

A detailed rock magnetic investigation has been carried out on Deep Sea Drilling Project (DSDP) pelagic sediments from the Central Equatorial Pacific. This comprises hysteresis and thermomagnetic measurements, Lowrie-Fuller test and, for the first time, ferromagnetic resonance (FMR). Nearly stochiometric magnetite in two grain size fractions, single domain (SD) and multi domain (MD), has been deduced to be the carrier of magnetic remanence. Comparatively strong paramagnetic contributions are carried by pyrite, being identified by X-ray analysis. The statistical analysis of paleomagnetic parameters (NRM, MDF, initial susceptibility, Königsberger ratio Q) from a large number (> 1000) of samples, supported by hysteresis measurements, indicates a latitude and sedimentation rate dependent ratio of SD/MD grains. Possible sources for the magnetic constituents are discussed in terms of bacterial, volcanic, meteoritic and authigenic origin.

Theories of magnetism. Report of the Committee on theories of magnetism of the National research council,

Mode of access: Internet.

Electricity and magnetism /

"Printed in Great Britain."

A course of simple experiments in magnetism & electricity /

Mode of access: Internet.

Second stage magnetism & electricity; for the second stage examination of the board of education.

Mode of access: Internet.

Electricity and magnetism.

Mode of access: Internet.

Theory of magnetism, magnetic properties of materials and use of magnetic materials in instrumentation

Mode of access: Internet.

Research opportunities in magnetism for naval application : report on a workshop, June 2-4, 1986, Purdue University, West Lafayette, Indiana

Mode of access: Internet.

Vandeleur; or, Animal magnetism. A novel ...

Published anonymously.

Contributions to terrestrial magnetism [no.1-11].

v.12-15 not included.

Principles of electricity; an intermediate text in electricity and magnetism,

First published, June 1931. Reprinted, July 1932 ... August 1939."

Magnetism /

Mode of access: Internet.

A first book of electricity and magnetism for the use of elementary science ... and engineering students and general readers /

First published in 1891.