High-pressure magnetic susceptibility studies of spin-state transition in Fe(II) complexes

Usha, S.; Srinivasan, Raghavan; Rao, C. N. R.

doi:10.1016/0301-0104(85)87069-5

Cited by 39 publications

(14 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus, HS complexes were (partially) converted into LS species at room temperature in the solid state. Besides puzzling reverse transitions at very high pressures, which were not confirmed, subsequent magnetic susceptibility measurements unambiguously corroborated high‐pressure‐induced HS→LS transitions in [Fe II (phen) 2 (NCS) 2 ] and [Fe II (bipy) 2 (NCS) 2 ] at room temperature …”

Section: Pressure‐induced Spin‐crossovermentioning

confidence: 89%

How to Switch Spin‐Crossover Metal Complexes at Constant Room Temperature

Khusniyarov

2016

Chemistry A European J

115

View full text Add to dashboard Cite

Spin-crossover metal complexes represent a highly promising class of molecular switches, the diverse physicochemical properties of which can be reversibly changed by different physical and chemical stimuli. One of the most interesting and examined features of these materials is the change of magnetic properties by changing the temperature or by irradiation with light at low temperatures. However, most prospective applications of such complexes require functioning at room temperature. This Concept article provides an overview about how the switching of spin-crossover metal complexes can be achieved at constant room temperature. The principles of switching by different physical and chemical methods in solution and in the solid state are presented in an easy-to-read form for nonspecialists. These are further supported and clarified by examples from the literature. The overview might also be interesting for experts that target spin-crossover systems functioning at ambient conditions.

show abstract

Section: Pressure‐induced Spin‐crossovermentioning

confidence: 89%

How to Switch Spin‐Crossover Metal Complexes at Constant Room Temperature

Khusniyarov

2016

Chemistry A European J

115

View full text Add to dashboard Cite

show abstract

“…It is important that the validity of any such assumptions is evaluated in each case before application. Since the first report of high pressure magnetic susceptibility measurements of SCO solutions [12] and solids [26], there have been numerous studies of SCO materials under pressure using SQUID magnetometry, which will be largely covered in section 3 of this review. There are also some reports of DACs that have been optimised for use in squid magnetometers [103].…”

Section: Magnetic Measurementsmentioning

confidence: 99%

“…High-pressure investigations (primarily using Mössbauer spectroscopic detection) were then taken up by the groups of Gütlich, Long and König [21 41]. There was a renaissance of interest in the effect of "CO [42 77], involving studies using either clamp-type and helium gas cells coupled to magnetic susceptibility [26] and optical [49,60] detection methods or diamond anvil cells (DAC) in conjunction with X-ray spectroscopic [61,64,66,70] or X-ray diffraction [68,78] techniques. These and also some more recent studies that we will discuss have led to a range of experimental observations on several dozens of SCO compounds.…”

Section: Introductionmentioning

confidence: 99%

“…Ainsi, l'objectif principal du présent article est une mise au point sur les techniques utilisées pour l'étude des composés à transition de spin sous pressionillustrées par une sélection de résultats récents.the piston(s) in the desired position even after removing the cell from the press. These (relatively) small, autonomous cells are particularly popular because they can be easily combined with cryostats, magnetometers and other equipment [26,82,109]. While several designs, both home built and commercially available have been used in the study of SCO materials, the principle upon which they work is similar.…”

unclassified

See 1 more Smart Citation

Pressure effect investigations on spin-crossover coordination compounds

Gaspar

Molnár

Rotaru

et al. 2018

Comptes Rendus. Chimie

View full text Add to dashboard Cite

The piezo-chromic properties of spin crossover complexes have been recognized for a long time, with increasing pressure favouring the low spin state due to its smaller volume and therefore shifting the spin equilibrium towards higher temperatures and accelerating the relaxation at a given temperature. However, the interpretation and quantification of pressure induced changes have been several times compromised by the relatively poor and incomplete spectral and structural information provided by the detection methods or due to the experimental difficulties related to the need for hydrostatic conditions at low temperatures. The present review is therefore primarily focused on these experimental aspects of high pressure spin crossover research providing an overview of methods of pressure generation and associated detection methods as well as on selected recent results.Résumé: Les propriétés piézo-chromiques de complexes à transition de spin ont été identifiées depuis longtemps. Du point de vue théorique, l'application d'une pression favorise l'état bas spin, de plus petit volume. Ainsi les températures de transition augmentent et les cinétiques de relaxation s'accélèrent sous pression. Toutefois, l'interprétation et la quantification des modifications induites par la pression restent un challenge en raison de la difficulté d'obtenir des données structurales et spectrales fiables dans des conditions de pression hydrostatique. Ceci est d'autant plus vrai lorsque les hautes pressions et les basses températures doivent être combinées. Ainsi, l'objectif principal du présent article est une mise au point sur les techniques utilisées pour l'étude des composés à transition de spin sous pressionillustrées par une sélection de résultats récents.the piston(s) in the desired position even after removing the cell from the press. These (relatively) small, autonomous cells are particularly popular because they can be easily combined with cryostats, magnetometers and other equipment [26,82,109]. While several designs, both home built and commercially available have been used in the study of SCO materials, the principle upon which they work is similar. In general the sample is placed in a Teflon capsule J Rotaru et al. have been analysed the thermal behaviour of the spin transition complexes [FexZn1-x(btr)2(NCS)2]H2O (for x=0.6 and x=1) by diffuse reflectivity measurements, under constant pressure in the range 1-1600 bars obtained with a gas pressure cell [186]. I J , as shown in Figure 24.

show abstract

“…229 Pressure as well as temperature variations of spin-state transitions in Fe (11) complexes have been analysed in terms of such models. 224,225,230 Coupling of the d-electrons and the lattice has been treated as a Jahn-Teller coupling in Kambara's Specific inclusion of elastic terms in this model appears to improve the quality of the Dynamical models using terms related to the elastic energy in the Hamiltonian and mixing of the high-spin and low-spin states by an ion cage mode have been examined.233 7.4 Transitions in Superconductors -Much money has been expended the world over in pushing up the superconducting T, and with much d i ~a p p o i n t m e n t . ~~~…”

Section: 2mentioning

confidence: 99%