Search results for "complex"

Interplay between spin-crossover and luminescence in a multifunctional single crystal iron( ii ) complex: towards a new generation of molecular senso…

2019

Multifunctional mononuclear iron( ) complex coordinated with six phosphorescent ligands exhibiting correlated spin-crossover transition and enhanced fluorescence.

Photomagnetic properties of an Iron(II) low-spin complex with an unusually long-lived metastable LIESST state

2007

A comprehensive study of the photomagnetic behavior of the [Fe(L222N5)(CN)2].H2O complex has been carried out. This complex is characterized by a low-spin (LS) iron(II)-metal center up to 400 K and exhibits at 10 K the well-known Light-Induced Excited Spin State Trapping (LIESST) effect. The critical LIESST temperature (T(LIESST)) has been measured to be 105 K. The kinetics of the transition from the metastable high-spin (HS) state to the low-spin state have been determined and used for reproducing the experimental T(LIESST) curve. This study represents a second example of a fully low-spin iron(II)-metal complex up to 400 K, which can be photoexcited at low temperature with an atypical long…

Ammonia Activation by a Nickel NCN-Pincer Complex featuring a Non-Innocent N-Heterocyclic Carbene: Ammine and Amido Complexes in Equilibrium

2015

A Ni0-NCN pincer complex featuring a six-membered N-heterocyclic carbene (NHC) central platform and amidine pendant arms was synthesized by deprotonation of its NiII precursor. It retained chloride in the square-planar coordination sphere of nickel and was expected to be highly susceptible to oxidative addition reactions. The Ni0 complex rapidly activated ammonia at room temperature, in a ligand-assisted process where the carbene carbon atom played the unprecedented role of proton acceptor. For the first time, the coordinated (ammine) and activated (amido) species were observed together in solution, in a solvent-dependent equilibrium. A structural analysis of the Ni complexes provided insig…

Self-Representation of Children Suffering from Congenital Heart Disease and Maternal Competence

2013

Background: Child development may be subject to forms of motor, physical, cognitive and self-representation impairments when complex congenital heart disease (CHD) occurs. In some cases, inadequacy of both self-representation as well as the family system are displayed. It seems to be important to search the likely internal and external resources of the CHD child, and the possible connections among such resources, which may help him/her to manage his/her own risk condition. Design and Methods: The research project inquires the possible resources related to the self-representation and self-esteem levels of the CHD child, and those related to maternal self-perception as competent mothers. A gr…

Responses of microbial activity and decomposer organisms to contamination in microcosms containing coniferous forest soil.

2002

Soil respiration from microcosms contaminated with pentachlorophenol, 2-ethanolhexanoate, creosote, CuSO4, and benomyl was measured in order to evaluate usefulness of soil microcosms and microbial respiration rate monitoring as a toxicity test in soils with high organic matter content. Coniferous forest soil and its organisms were used as test objects. In addition, how a short-term low temperature period including frost affects respiration dynamics in stressed soils was studied, i.e., whether contaminants reduce resistance of the community to other (also natural) stresses. In addition, at the end of the experiment, effects of contaminants on faunal and microbial community structures were an…

One-dimensional oxalato-bridged copper(II) complex possessing two structurally different metallic centres

2001

Abstract The crystal structure of the oxalato-bridged copper(II) compound [Cu2(μ-ox)2(ampy)3]n 1 (ox=oxalate dianion, ampy=2-amino-3-methylpyridine) consists of infinite corrugated one-dimensional chains in which two types of copper(II) centres, five- and six-coordinated, are bridged sequentially by asymmetric bis-bidentate oxalato ligands. Magnetic susceptibility measurements show the occurrence of a significant intrachain antiferromagnetic coupling (J=−22.9 cm −1 ) .

Selective Encapsulation and Enhancement of the Emission Properties of a Luminescent Cu(I) Complex in Mesoporous Silica

2018

Solvent directs the dimensionality of Cu-dicyanoimidazoles

2022

In this paper, we report one-pot reactions of the same reactants 4,5-dicyanoimidazole and CuI in different solvents. In pure MeCN, the reaction resulted in previously reported MOF structure [Cu(4,5-dicyanoimidazole)]n.(MeCN)0.5n (1). On the other hand, when MeCN/MeOH solvent mixture was used, a new coordination polymer [Cu(4,5-dicyanoimidazole)(MeCN)(CuI)]n (2) was formed. The crystallization yielded very different structures as determined by X-ray crystallography. In 1, the solvent molecule acetonitrile occupies the MOF pores via weak interactions, but in 2 it is coordinated to the metal center. Computational DFT calculations and topological charge density analysis were utilized to explore…

Bridging vs. chelating coordination modes of vinylsilanes in CuI π-Complexes: Structure and stability

2014

Two new copper(I) olefin complexes, [Cu6Cl6(MTrVS)2] (1) and [Cu2Cl2(DMVSP)2] (2), of tridentate bridging methyltrivinylsilane (MTrVS) and bidentate chelating 2-[dimethyl(vinyl)silyl]pyridine (DMVSP) have been synthesized and characterized by single-crystal X-ray structure analysis, IR and 1H NMR spectroscopy. It has been shown that using the alkenylsilanes with required electronic properties, molecular symmetry and conformational flexibility, it is possible to control the formation of optimal copper(I) halide oligomers. The obtained results, together with relevant literature data, also illustrate how the coordination mode of vinylsilanes is related to Cu–(C=C) bond strengthening and, conse…

A strike-slip core complex from the Najd fault system, Arabian shield

2014

Metamorphic core complexes are usually thought to be associated with regional crustal extension and crustal thinning, where deep crustal material is exhumed along gently dipping normal shear zones oblique to the regional extension direction. We present a new mechanism whereby metamorphic core complexes can be exhumed along crustal-scale strike-slip fault systems that accommodated crustal shortening. The Qazaz metamorphic dome in Saudi Arabia was exhumed along a gently dipping jog in a crustal-scale vertical strike-slip fault zone that caused more than 25 km of exhumation of lower crustal rocks by 30 km of lateral motion. Subsequently, the complex was transected by a branch of the strike-sli…