Magnetism: General Introduction

摘要: One of the distinctive properties transition-metal compounds is presence unpaired electrons in partially filled d-shell which give rise to magnetic properties. The metal ions are therefore paramagnetic, means that they attracted by an applied field. paramagnetism has its origins both spin and orbital moments electrons. In general, passage from isolated coordination associated with quenching moment, paramagnetic can be described a first approximation considering contribution as perturbation on term. It unquenched makes measurement important tool for structural characterization compounds. fact measurements have long been used order obtain information. Magnetochemistry (Carlin, R. L. ; Springer-Verlag: Berlin, 1986; O’Connor, C. J. – Theory Experimentation Wiley: New York, 1972) was extensively developed 1950s conjunction impact quantum mechanics chemistry fundamental eighties there gradual shift simple all kinds cooperative phenomena, investigation complex zero-, one-, two-, three-dimensional molecule-based materials (de Jongh, J.; Miedema, A. Adv. Phys. 1974 , 23 1–260; Kahn, O. Molecular Magnetism VCH: Weinheim, 1993; Gatteschi, D.; O.; Miller, S.; Palacio, F., Eds. Magnetic Materials NATO ASI; Kluwer: Dordrecht, Netherlands, 1991). This interest accompanied progressive increase complexity techniques investigate early stages effective moment at room temperature enough, now it almost routine measure down liquid helium region below, d.c. a.c. mode. Sophisticated also single crystals.