Single-Molecule Magnets: Magnetization Relaxation and Quantum Tunneling in Dodecanuclear Manganese Complexes

Resonant magnetization tunneling inMn12acetate: The absence of inhomogeneous hyperfine broadening

“…The molecular magnet Mn 12 acetate, with spin 10 and large uniaxial anisotropy, has garnered much attention since its hysteresis loop was found to exhibit steps at regular intervals of magnetic field [1]. This phenomenon, now confirmed by other experiments on this [2][3][4][5][6] and other materials [7][8][9][10], has been interpreted as a manifestation of resonant tunneling of the magnetization, first suggested to occur in this system in Refs. 11 and 12.…”

A toolbox of building blocks, linkers and crystallisation methods used to generate single-chain magnets

“…Hacac acetylacetone H 2 HO-bdc 5-hydroxy-1,3-benzenedicarboxylic acid acetic acid H 2 ox oxalic acid TCNQ tetracyanoquinodimethane TCNE tetracyanoethylene 4,4-Hopybz 4-(4-pyridyl)benzoic acid N-oxide (R)-H 2 pabn (R)-N (2),N(2 )-bis(pyridin-2-ylmethyl)-1, -binaphthyl-2,2 -diamine Hpao pyridine-2-aldoxime Hpcq 8-(pyridine-2-carboxamido)quinolone 2,5-H 2 pidc pyridine-2,5-dicarboxylic acid Hpiv pivalic acid Hpyoa 2-(pyridin-3-yloxy)-acetic acid Ph phenyl group py pyridine pzTp tetrakis(pyrazolyl)borate Hsalox 2-hydroxysalicylaldoxime 3-tBu-5-MeH 2 salox 2-hydroxy-3-tert-butyl-5-methoxysalicylaldoxime tBu-H 2 salox 3,5-di-tert-butylsalicylaldoxime H 2 saltmen N,N -(1,1,2,2-tetramethylethylene)bis (salycylideneimine) 5-TMAMH 2 salen N,N -ethylenebis (5-trimethylammoniomethyl)bis(salicylideneimine) H 2 TPP meso-tetraphenylporphyrin H 2 TBPP meso-tetra(4-biphenyl)porphyrin H 2 TFPP tetrakis(ortho-fluorophenyl)porphyrin trans-1,2-H 2 chdc trans-1,2-cyclohexanedicarboxylic acid Htzpo 4-(5-tetrazole)pyridine-N-oxide tp tris(pyrazolyl)borate tp* hydridotris(3,5-dimethylpyrazol-1-yl)borate H 2 tpfc 5,10,15-tris(pentafluorophenyl)corrole H 2 thdz 4,4 -(((1,3,4-thiadiazole-2,5-diyl)bis(sulfanediyl))bis(methylene))dibenzoic acid 2,4,6-tmpa N-2,4,6-trimethylphenyloxamate…”

“…The first SMM was discovered in 1993 by Gatteschi, Caneschi and coworkers [1], and the name single-molecule magnet (SMM) was suggested to describe and emphasise the importance of these systems, which exhibit properties associated with traditional macroscopic magnets but on a molecular level: below a blocking temperature (T B ), they can retain the magnetisation after removal of the external magnetic field [2]. The reason behind this behaviour is, in the simplest case, the preference of the molecule for an easy axis of the magnetisation, due to some anisotropy being present in the molecule.…”

Quantum tunneling and classical barrier reduction for a mesoscopic spin

“…4 This phenomenon has been verified in other experiments on the same material [5][6][7][8][9] and there is now some evidence for it in other systems. 10,11 While there have been many semiclassical treatments of tunneling in magnetic systems, [12][13][14] such approaches have turned out to be unnecessary for Mn 12 , which with Sϭ10 is easily tractable by more precise methods. The dynamics of Mn 12 have been quantitatively described 4,5,8 by a simple Hamiltonian:…”