Spin crossover and reversible single-crystal to single-crystal transformation behaviour in two cyanide-bridged mixed-valence {Fe III 2 Fe II 2 } clusters

Chunyang Zheng; Juping Xu; Feng Wang; Jun Tao; Dongfeng Li

doi:10.1039/c6dt03436e

Spin crossover and reversible single-crystal to single-crystal transformation behaviour in two cyanide-bridged mixed-valence {Fe III 2 Fe II 2 } clusters

Chunyang Zheng, Juping Xu, Feng Wang, Jun Tao, Dongfeng Li^*

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

46 Citations (Scopus)

Abstract

The reactions of tricyanometallate precursors, (Ph₃PMe)[(Tp^4-Me)Fe(CN)₃·0.5CH₃CN] (1) (Tp^4-Me = tri(4-methyl-pyrazol-1-yl)borate) and (NBu₄)[(^MeTp)Fe(CN)₃] (^MeTp = methyltris(pyrazolyl)borate) with the presence of the tetradentate tpa ligand (tpa = tris(2-pyridylmethyl)amine) and Fe(ClO₄)₂·6H₂O afford two new cyano-bridged mixed-valence {FeIII2FeII2} molecular squares: [(Tp^4-Me)Fe^III(CN)₃]₂[Fe^II(tpa)]₂·2ClO₄·H₂O (2·H₂O) and [(^MeTp)Fe^III(CN)₃]₂[Fe^II(tpa)]₂·2ClO₄·CH₃OH (3·CH₃OH). Solvent-exchange compounds of 3·CH₃OH, [(^MeTp)Fe^III(CN)₃]₂[Fe^II(tpa)]₂·2ClO₄·2H₂O (3·2H₂O), and their solvent-free form (2 and 3) are also obtained, respectively. The spin crossover (SCO) properties of all compounds are confirmed by detailed structural analyses of the coordination environments of the Fe^II centres and magnetic susceptibility measurements. All compounds exhibit SCO behaviour near room temperature (T_1/2 = 320 K for 2·H₂O; 302 K for 2; 292 K for 3·CH₃OH; 306 K for 3·2H₂O and 290 K for 3) and reversible single-crystal to single-crystal (SC-SC) transformations induced by guest desorption and resorption or solvent exchange. The transition temperature close to room temperature can be tuned by the dehydration and re-hydration processes. The structure-property analysis discloses that the distorted {Fe₄(μ-CN)₄} core and deviations of bent ∠Fe-NC angles play a key role in tuning the transition temperature of these similar mixed-valence {FeIII2FeII2} complexes.

Original language	English
Pages (from-to)	17254-17263
Number of pages	10
Journal	Dalton Transactions
Volume	45
Issue number	43
DOIs	https://doi.org/10.1039/c6dt03436e
Publication status	Published - 2016
Externally published	Yes

Access to Document

10.1039/c6dt03436e

Cite this

@article{764469c043c248c3b2de2242805e5b37,

title = "Spin crossover and reversible single-crystal to single-crystal transformation behaviour in two cyanide-bridged mixed-valence {Fe III 2 Fe II 2 } clusters",

abstract = "The reactions of tricyanometallate precursors, (Ph3PMe)[(Tp4-Me)Fe(CN)3·0.5CH3CN] (1) (Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate) and (NBu4)[(MeTp)Fe(CN)3] (MeTp = methyltris(pyrazolyl)borate) with the presence of the tetradentate tpa ligand (tpa = tris(2-pyridylmethyl)amine) and Fe(ClO4)2·6H2O afford two new cyano-bridged mixed-valence {FeIII2FeII2} molecular squares: [(Tp4-Me)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·H2O (2·H2O) and [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·CH3OH (3·CH3OH). Solvent-exchange compounds of 3·CH3OH, [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·2H2O (3·2H2O), and their solvent-free form (2 and 3) are also obtained, respectively. The spin crossover (SCO) properties of all compounds are confirmed by detailed structural analyses of the coordination environments of the FeII centres and magnetic susceptibility measurements. All compounds exhibit SCO behaviour near room temperature (T1/2 = 320 K for 2·H2O; 302 K for 2; 292 K for 3·CH3OH; 306 K for 3·2H2O and 290 K for 3) and reversible single-crystal to single-crystal (SC-SC) transformations induced by guest desorption and resorption or solvent exchange. The transition temperature close to room temperature can be tuned by the dehydration and re-hydration processes. The structure-property analysis discloses that the distorted {Fe4(μ-CN)4} core and deviations of bent ∠Fe-NC angles play a key role in tuning the transition temperature of these similar mixed-valence {FeIII2FeII2} complexes.",

author = "Chunyang Zheng and Juping Xu and Feng Wang and Jun Tao and Dongfeng Li",

note = "Publisher Copyright: {\textcopyright} 2016 The Royal Society of Chemistry.",

year = "2016",

doi = "10.1039/c6dt03436e",

language = "English",

volume = "45",

pages = "17254--17263",

journal = "Dalton Transactions",

issn = "1477-9226",

publisher = "Royal Society of Chemistry",

number = "43",

}

TY - JOUR

T1 - Spin crossover and reversible single-crystal to single-crystal transformation behaviour in two cyanide-bridged mixed-valence {Fe III 2 Fe II 2 } clusters

AU - Zheng, Chunyang

AU - Xu, Juping

AU - Wang, Feng

AU - Tao, Jun

AU - Li, Dongfeng

PY - 2016

Y1 - 2016

N2 - The reactions of tricyanometallate precursors, (Ph3PMe)[(Tp4-Me)Fe(CN)3·0.5CH3CN] (1) (Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate) and (NBu4)[(MeTp)Fe(CN)3] (MeTp = methyltris(pyrazolyl)borate) with the presence of the tetradentate tpa ligand (tpa = tris(2-pyridylmethyl)amine) and Fe(ClO4)2·6H2O afford two new cyano-bridged mixed-valence {FeIII2FeII2} molecular squares: [(Tp4-Me)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·H2O (2·H2O) and [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·CH3OH (3·CH3OH). Solvent-exchange compounds of 3·CH3OH, [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·2H2O (3·2H2O), and their solvent-free form (2 and 3) are also obtained, respectively. The spin crossover (SCO) properties of all compounds are confirmed by detailed structural analyses of the coordination environments of the FeII centres and magnetic susceptibility measurements. All compounds exhibit SCO behaviour near room temperature (T1/2 = 320 K for 2·H2O; 302 K for 2; 292 K for 3·CH3OH; 306 K for 3·2H2O and 290 K for 3) and reversible single-crystal to single-crystal (SC-SC) transformations induced by guest desorption and resorption or solvent exchange. The transition temperature close to room temperature can be tuned by the dehydration and re-hydration processes. The structure-property analysis discloses that the distorted {Fe4(μ-CN)4} core and deviations of bent ∠Fe-NC angles play a key role in tuning the transition temperature of these similar mixed-valence {FeIII2FeII2} complexes.

AB - The reactions of tricyanometallate precursors, (Ph3PMe)[(Tp4-Me)Fe(CN)3·0.5CH3CN] (1) (Tp4-Me = tri(4-methyl-pyrazol-1-yl)borate) and (NBu4)[(MeTp)Fe(CN)3] (MeTp = methyltris(pyrazolyl)borate) with the presence of the tetradentate tpa ligand (tpa = tris(2-pyridylmethyl)amine) and Fe(ClO4)2·6H2O afford two new cyano-bridged mixed-valence {FeIII2FeII2} molecular squares: [(Tp4-Me)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·H2O (2·H2O) and [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·CH3OH (3·CH3OH). Solvent-exchange compounds of 3·CH3OH, [(MeTp)FeIII(CN)3]2[FeII(tpa)]2·2ClO4·2H2O (3·2H2O), and their solvent-free form (2 and 3) are also obtained, respectively. The spin crossover (SCO) properties of all compounds are confirmed by detailed structural analyses of the coordination environments of the FeII centres and magnetic susceptibility measurements. All compounds exhibit SCO behaviour near room temperature (T1/2 = 320 K for 2·H2O; 302 K for 2; 292 K for 3·CH3OH; 306 K for 3·2H2O and 290 K for 3) and reversible single-crystal to single-crystal (SC-SC) transformations induced by guest desorption and resorption or solvent exchange. The transition temperature close to room temperature can be tuned by the dehydration and re-hydration processes. The structure-property analysis discloses that the distorted {Fe4(μ-CN)4} core and deviations of bent ∠Fe-NC angles play a key role in tuning the transition temperature of these similar mixed-valence {FeIII2FeII2} complexes.

UR - http://www.scopus.com/inward/record.url?scp=84994274911&partnerID=8YFLogxK

U2 - 10.1039/c6dt03436e

DO - 10.1039/c6dt03436e

M3 - Article

AN - SCOPUS:84994274911

SN - 1477-9226

VL - 45

SP - 17254

EP - 17263

JO - Dalton Transactions

JF - Dalton Transactions

IS - 43

ER -

Spin crossover and reversible single-crystal to single-crystal transformation behaviour in two cyanide-bridged mixed-valence {Fe III 2 Fe II 2 } clusters

Abstract

Access to Document

Other files and links

Fingerprint

Cite this