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1.
本文制备了2种新的离子对配合物[M(phen)3][Ni(mnt)2](phen=1,10-菲咯啉,mnt2-=马来二腈二硫烯;M2+=Ni2+,1;Fe2+,2),并进行了结构表征。2种离子对配合物晶体的空间群都为P21/n,具有类似的晶胞参数和堆积结构。紫外可见-近红外光谱显示在近红外区域没有出现明显的吸收峰。在2到400 K的温度范围内,化合物1表现居里-外斯型的顺磁性行为,并在磁性[Ni(phen)3]2+离子之间存在弱的反铁磁作用,而且在八面体配位环境下Ni2+离子自旋基态S=1。化合物2在40 K向上显示抗磁性,意味[Fe(phen)3]2+离子处于低自旋态。低于40 K时,弱居里尾巴可能是由于小部分顺磁性[Ni(mnt)2]-杂质导致的。  相似文献   

2.
合成并表征了两种新的离子对化合物(BMIB)[(Ni(mnt)2]2(1)和(BMIO)[(Ni(mnt)2)]2(2)(其中mnt2-=马来二氰基二硫烯,BMIB=1,4-bis(1-methylimidazolium)butane,BMIO=1,8-bis(1-methylimidazolium)octane)。在化合物1中,[Ni(mnt)2]-阴离子排列形成阴离子三聚体以及与阳离子交替排列形成阴、阳离子混合柱。化合物2的堆积结构与化合物1不同,阴、阳离子堆积成非等间距的阴、阳离子柱。化合物1和2分别在861和857 nm近红外波段处出现较强的近红外吸收。电化学性质研究结果表明,2个化合物均出现了两对不可逆的电化学氧化/还原过程,且平衡阳离子的烷基链长显著影响化合物的氧化、还原电极电势。变温磁化率测量表明,在2~400 K温度范围内,化合物1表现出弱的顺磁性质,变温摩尔磁化率遵循简单的Curie-Weiss定律。化合物2表现出低维反铁磁交换自旋体系磁化率特征。  相似文献   

3.
合成并表征了一种新的离子对化合物[4-NH2-Py][TCNQ](其中4-NH2-Py+是4-氨基吡啶阳离子,TCNQ-为7,7,8,8-四氰基对苯二醌二甲烷自由基阴离子)。在该离子对化合物晶体中,2个TCNQ-离子形成了面对面堆积的二聚体;阴离子中的氰基分别和阳离子上的氨基、吡啶质子化氮原子之间存在非常强的分子间氢键。通过氢键作用,相邻的TCNQ-二聚体被阳离子连成三维氢键网络。变温磁化率测量表明,在2~400 K温度范围内,该离子对化合物表现为抗磁性。在密度泛函理论框架下,用对称性破损方法计算了化合物晶体中π二聚体内以及通过氢键连接的相邻的TCNQ-离子之间的磁交换常数,发现π二聚体内存在非常强的反铁磁交换作用,与之相比,通过氢键连接的TCNQ-离子之间的磁交换作用可以忽略。π二聚体内强反铁磁交换作用(J/kB≈1805 K)导致了该化合物基本表现为抗磁性。  相似文献   

4.
本工作设计和合成了十个由夹心型金属有机化合物阳离子与金属二硫醇配合物[M(mnt)2]阴离子组成的金属有机盐类化合物:(M'Cp2)[M(mnt)2]或[FeCp(Tol)2][M(mnt)2]其中M=Ni, Pd, Co, Cu或Zn, M'=Fe或Co Cp代表环戊二烯基; Tol代表甲苯; mnt代表, 通过元素分析, IR和NMR对化合物进行表征, 测定了[FeCp(Tol)]2[Ni(mnt)2]的单晶结构。Mossbauer谱和AESR表明(FeCp2)[Ni(mnt)2]是个混合化合物, 提出了该化合物的生成反应机理。测定了所有化合物的固体电导率和部分化合物的固体磁学性质。  相似文献   

5.
本工作设计和合成了十个由夹心型金属有机化合物阳离子与金属二硫醇配合物[M(mnt)2]阴离子组成的金属有机盐类化合物:(M'Cp2)[M(mnt)2]或[FeCp(Tol)2][M(mnt)2]其中M=Ni, Pd, Co, Cu或Zn, M'=Fe或Co Cp代表环戊二烯基; Tol代表甲苯; mnt代表, 通过元素分析, IR和NMR对化合物进行表征, 测定了[FeCp(Tol)]2[Ni(mnt)2]的单晶结构。Mossbauer谱和AESR表明(FeCp2)[Ni(mnt)2]是个混合化合物, 提出了该化合物的生成反应机理。测定了所有化合物的固体电导率和部分化合物的固体磁学性质。  相似文献   

6.
二硫烯过渡金属配合物因特殊的结构和新颖的光、电、磁学等性质,多年来倍受化学家和材料学家重视[1,2].含[M(mnt)2]- (mnt为马来二氰基二硫烯,M 为 Ni、Pd、Pt和Fe等)配阴离子化合物NH4·Ni(mnt)2·H2O,发现低温下(<4.5 K)具有铁磁有序,是对二硫烯化学的新发展[3].  相似文献   

7.
合成并表征了两种新的离子对化合物(BMIB)[(Ni(mnt)2]2 (1)和(BMIO)[(Ni(mnt)2)]2 (2)(其中mnt2-=马来二氰基二硫烯, BMIB=1, 4-bis(1-methylimidazolium)butane, BMIO=1, 8-bis(1-methylimidazolium)octane)。在化合物1中, [Ni(mnt)2]-阴离子排列形成阴离子三聚体以及与阳离子交替排列形成阴、阳离子混合柱。化合物2的堆积结构与化合物1不同, 阴、阳离子堆积成非等间距的阴、阳离子柱。化合物1和2分别在861和857 nm近红外波段处出现较强的近红外吸收。电化学性质研究结果表明, 2个化合物均出现了两对不可逆的电化学氧化/还原过程, 且平衡阳离子的烷基链长显著影响化合物的氧化、还原电极电势。变温磁化率测量表明, 在2~400 K温度范围内, 化合物1表现出弱的顺磁性质, 变温摩尔磁化率遵循简单的Curie-Weiss定律。化合物2表现出低维反铁磁交换自旋体系磁化率特征。  相似文献   

8.
合成了离子对配合物(NO2Q1)2[Ni(mnt)2],并用元素分析和红外光谱进行了表征.单晶结构分析结果表明三斜晶系,空间群p-1.晶胞参数a=8.2240(16)A,6=10.777(2)A,c=12.137(2)A,α=72.58(3).,β=72.82(3)°,γ=68.78(3)°,V=935.4(3)A3,Z=1.(NO2Ql)+和[Ni(mnt)2]2-分别形成了完全分立的柱状堆积结构.在阴离子堆积柱内,Ni(Ⅱ)离子形成了一维均匀链.阳离子间,比邻的芳环间存在弱的π…π作用.  相似文献   

9.
描述了两个具有管状氢键假想孔道结构的化合物[Ni(en)3][GeF6][JLG-1(Ni)]和[Co(en)3].[GeF6][JLG-1(Co)].在这两个结构中,[GeF6]2-阴离子与手性金属配合物阳离子[M(en)3]2+(M=Ni,Co)通过F…N之间复杂的弱氢键相互作用,在沿着63螺旋轴方向形成六方蜂窝状排布的管状氢键假想孔道.结构研究发现,配对的[GeF6]2阴离子和手性[M(en)3]2+阳离子同属于D3点群,这是JLG-1(Ni)和JLG-1(Co)形成管状氢键假想孔道的关键.这一研究成果对设计合成氢键假想孔道体系具有一定的指导意义.  相似文献   

10.
二氰基二硫烯(mnt和i-mnt)的金属配合物因其结构独特并呈现出特殊的光、电和磁学等性质,多年来引起科学家们广泛的关注[1-2].特别是在含Ni(mnt)2阴离子的离子对配合物中,功能阳离子的大小和构型改变可以导致Ni(mnt)2阴离子的重叠模式和堆积方式的变化,从而影响这类配合物的物理性能[3-5].为进一步探索取代苄基吡啶鎓离子中取代基团对1,2′-二氰基-1,2′-二硫烯镍配合物的结构的影响,我们在以前工作的基础上[6-8],合成了1种新的1,2′-二氰基-1,2′-二硫镍(II)离子对配合物[Bz(Me)Py]2[Ni(mnt)2],用元素分析、红外光谱和X-射线衍射表征了其组成和结构,讨论了配合物晶体中弱的相互作用.  相似文献   

11.
Pei WB  Wu JS  Tian ZF  Ren XM  Song Y 《Inorganic chemistry》2011,50(9):3970-3980
Three [1-N-(4'-R-benzyl)-4-aminopyridinium][Pt(mnt)(2)] compounds were structurally and magnetically characterized, where the substituent was attached to the para-position of the phenyl ring (R = CN (1), Cl (2), and H (3); mnt(2-) = maleonitriledithiolate). 1 and 2 crystallized in the monoclinic space group P2(1)/c, with the cations and anions forming segregated columnar stacks. Their structural differences involved two aspects: (1) both anion and cation stacks were regular in 1 and irregular in 2; (2) the neighboring cations were arranged in the boat-type pattern in 1, whereas these cations were in the chair-type pattern in 2 within the cation stack. 3 belonged to the triclinic space group P ?1, where the anions were assembled into the stack with a tetrameric [Pt(mnt)(2)](-) subunit, but the cations did not form the columnar stack. Magnetic measurements disclosed that a spin-Peierls-type transition occurred around 240 K for 1, whereas a long-range, antiferromagnetic ordering took place at about 5.8 K, and a metamagnetic phenomenon was observed with H(C) ≈ 1000 Oe for 2; 3 showed very strong antiferromagnetic interactions with diamagnetism in the temperature range 5-300 K. Combined with our previous studies, the correlation between the stacking pattern of benzylpyridinium derivatives in a cation stack and the spin-Peierls-type transition is discussed for the series of quasi-1-D [M(mnt)(2)](-) (M = Ni, Pd and Pt) compounds.  相似文献   

12.
Enantiomerically pure dithiolene complexes NBu4[Ni[(R,R)-diotte)2] and NBu4[Ni((S,S)-diotte]2] (diotte2- = a 1,3-dioxolane-tetrathiaethylene), were prepared from the corresponding enantiomers of a diotte2- precursor. The structure of the precursor was solved by single-crystal X-ray analysis; desulfurization afforded a novel tetrathiafulvalene derivative. Combination of the complex monoanion with the enantiomers of the viologen derivative bis(2-methyl-3-hydroxypropyl)-4,4'-dipyridinium (HiBV2+) afforded enantiomeric and diastereomeric ion-pair complexes of the type HiBV[Ni(diotte)2]2. For comparison, the analogous compounds A[Ni(diotte)2]2, (A2+ = methyl (MV2+), octyl (OV2-), stearyl (StV2+) viologen or two 2,2'-bipyridinium acceptors), HiBV-[Ni(diotte)L] [L = mnt2- (maleonitrile-1,2-dithiolate), dmit2- (2-thioxo-1,3-dithiol-4,5-dithiolate)], MV[Ni(dmit)2)]2, [Ni(diotte)2], and [Ni(diotte)(dmit)] were synthesized. An X-ray powder diffraction structural analysis of MV-[Ni(dmit)2)]2 revealed the presence of mixed stacks that contain the sequence anion-anion-cation. While no short contacts are observable within a stack, these are observed between the stacks for the dication-anion interaction by short S...H distances in the range of 2.77 to 2.86 A, and for the anion-anion interaction short S...S distances of 3.55 to 3.65 A. In agreement with the absence of intrastack interactions, no ion-pair charge-transfer band can be detected in this and the other complexes. ESR and UV/Vis data suggest that in [Ni(diotte)2]- electron delocalization is less pronounced than in the corresponding mnt2- and dmit2- complexes. The specific electrical conductivity (sigma) of pressed powder pellets ranges from 10(-2) to 10(-12) ohm(-1) cm(-1) and in all cases increases with increasing temperature (293 - 393 K) according to an Arrhenius law. Corresponding activation energies vary from 0.14 to 0.93 eV and increase linearly with log a for structurally similar ion pairs. Charge generation is postulated to occur by disproportionation of the monoanion as suggested by the almost linear increase of log(sigma) with decreasing disproportionation energy. The conductivity of diastereomers of ions with two unlike configurations like [(S,S)-HiBV]-[Ni[(R,R)-diotte]2]2 (1.1 x 10(-1) ohm(-1) cm(-1)) is one to two orders of magnitude higher as compared to the diastereomers with two like-configured ions.  相似文献   

13.
The syntheses, structural characterizations and magnetic behaviors of three new complexes, 1-(3',4',5'-trifluorobenzyl)pyridinium [M(mnt)2]- [M = Ni (1), Pd (2) or Pt (3)], are reported. These complexes are isomorphous and their prominent structural character is that the [M(mnt)2]- anions form columnar stacks, in which the dimerization was observed. Complexes 2 and 3 are diamagnetic, while 1 possesses an energy gap of 2474 K. For crystal 4, 1-(4'-fluorobenzyl)pyridinium [Ni(mnt)2] (its structure and magnetic susceptibility were briefly reported earlier), the magnetic behavior can be divided into two regimes, namely, weakly ferromagnetic coupling above 93 K and strongly antiferromagnetic coupling below 93 K. A transition occurs at 93 K which switches the magnetic exchange nature from ferromagnetic to antiferromagnetic. A sharp thermal abnormality with lambda-shape, associated with the transition, appears from its heat capacity measurement to indicate that the transition is first order. The temperature dependences of the superlattice diffractions revealed the existence of the pretransitional phenomena up to at least 140 K. The unusual magnetic behavior of 4, such as the origin of the ferromagnetic interaction in the high temperature phase and what causes the spin transition, are discussed further.  相似文献   

14.
New heterospin complexes have been obtained by combining the binuclear complexes [{Cu(H(2)O)L(1)}Ln(O(2)NO)(3)] or [{CuL(2)}Ln(O(2)NO)(3)] (L(1) = N,N'-propylene-di(3-methoxysalicylideneiminato); L(2) = N,N'-ethylene-di(3-methoxysalicylideneiminato); Ln = Gd(3+), Sm(3+), Tb(3+)), with the mononuclear [CuL(1)(2)] and the nickel dithiolene complexes [Ni(mnt)(2)](q)- (q = 1, 2; mnt = maleonitriledithiolate), as follows: (1)infinity[{CuL(1)}(2)Ln(O(2)NO){Ni(mnt)(2)}].Solv.CH(3)CN (Ln = Gd(3+), Solv = CH(3)OH (1), Ln = Sm(3+), Solv = CH(3)CN (2)) and [{(CH(3)OH)CuL(2)}(2)Sm(O(2)NO)][Ni(mnt)(2)] (3) with [Ni(mnt)2]2-, [{(CH(3)CN)CuL(1)}(2)Ln(H(2)O)][Ni(mnt)(2)]3.2CH(3)CN (Ln = Gd(3+) (4), Sm(3+) (5), Tb(3+) (6)), and [{(CH(3)OH)CuL(2)}{CuL(2)}Gd(O(2)NO){Ni(mnt)(2)}][Ni(mnt)(2)].CH(2)Cl(2) (7) with [Ni(mnt))(2]*-. Trinuclear, almost linear, [CuLnCu] motifs are found in all the compounds. In the isostructural 1 and 2, two trans cyano groups from a [Ni(mnt)2]2- unit bridge two trimetallic nodes through axial coordination to the Cu centers, thus leading to the establishment of infinite chains. 3 is an ionic compound, containing discrete [{(CH(3)OH)CuL(2)}(2)Sm(O(2)NO)](2+) cations and [Ni(mnt)(2)](2-) anions. Within the series 4-6, layers of discrete [CuLnCu](3+) motifs alternate with stacks of interacting [Ni(mnt)(2)](*-) radical anions, for which two overlap modes, providing two different types of stacks, can be disclosed. The strength of the intermolecular interactions between the open-shell species is estimated through extended Hückel calculations. In compound 7, [Ni(mnt)(2)](*-) radical anions coordinate group one of the Cu centers of a trinuclear [Cu(2)Gd] motif through a CN, while discrete [Ni(mnt)(2)](*-) units are also present, overlapping in between, but also with the coordinated ones. Furthermore, the [Cu(2)Gd] moieties dimerize each other upon linkage by two nitrato groups, both acting as chelate toward the gadolinium ion from one unit and monodentate toward a Cu ion from the other unit. The magnetic properties of the gadolinium-containing complexes have been determined. Ferromagnetic exchange interactions within the trinuclear [Cu(2)Gd] motifs occur. In the compounds 4 and 7, the [Ni(mnt)(2)](*-) radical anions contribution to the magnetization is clearly observed in the high-temperature regime, and most of it vanishes upon temperature decrease, very likely because of the rather strong antiferromagnetic exchange interactions between the open-shell species. The extent of the exchange interaction in the compound 7, which was found to be antiferromagnetic, between the coordinated Cu center and the corresponding [Ni(mnt)(2)](*-) radical anion, bearing mostly a 3p spin type, was estimated through CASSCF/CASPT2 calculations. Compound 6 exhibits a slow relaxation of the magnetization.  相似文献   

15.
The crystal structures and magnetic properties were investigated experimentally and theoretically for two S = ? spin chain complexes, which consist of [M(mnt)(2)](-) (M = Pt for 1 or Pd for 2) with 1-(4'-bromo-2'-flurobenzyl)-4-aminopyridinium (1-BrFBz-4-NH(2)Py(+)). The 1-BrFBz-4-NH(2)Py(+) cations exhibit different molecular conformations and arrangements in 1 and 2; the [M(mnt)(2)](-) anions form regular stacks in 1, whereas they form irregular stacks in 2. In addition, the intermolecular interactions between the [M(mnt)(2)](-) anions and cations are also different from each other in the crystals of 1 and 2. Complex 1 shows the magnetic characteristics of a low-dimensional antiferromagnetic coupling spin system with a spin-Peierls-type transition around 7 K, and complex 2 exhibits diamagnetism over the temperature range of 5-300 K. Theoretical analyses, based on the calculations for the charge density distributions of [Pt(mnt)(2)](-) and [Pd(mnt)(2)](-) anions and the magnetic exchange constants within the anion spin chains, addressed the diverse molecular alignments in the crystals of 1 and 2 and distinct magnetic behaviors between 1 and 2.  相似文献   

16.
合成了一种新的含取代苄基三苯基鏻的马来二氰基二硫烯镍配合物[ClBzTPP]2[Ni(mnt)2].H2O([ClBzTPP]+代表对氯苄基三苯基鏻阳离子,mnt2-代表马来二氰基二硫烯阴离子).配合物为三斜晶系,空间群P墿,晶胞参数为a=1.058 5(2)nm,b=1.108 9(2)nm,c=1.157 0 nm,α=81.98(1)°,β=84.95(1)°,γ=84.45(1)°,V=1.369 1(4)nm3,Z=1,最终一致性因子R=0.058 4.该配合物由2个[ClBzT-PP]+阳离子,1个[Ni(mnt)2]2-阴离子和1个H2O组成.其结构特点是配合物中的[ClBzTPP]+阳离子和Ni(mnt)22-阴离子沿c轴方向堆积成柱,并通过C—H…S,C—H…π,C—H…Ni氢键和π-π堆积作用形成了二维网状结构.  相似文献   

17.
A new ion-pair complex, [TTF][Pd(mnt)2] (1), where TTF+ =?tetrathiafulvalene and mnt2??=?maleonitriledithiolate, was synthesized and characterized structurally. Compound 1 crystallizes in triclinic space group P-1, with a?=?8.008(5)?Å, b?=?11.333(8)?Å, c?=?11.373(6)?Å, α?=?108.112(7)°, β?=?91.550(5)°, γ?=?95.232(5)°, and V?=?975.2(11)?Å3. The [TTF]+ cations (C) and [Pd(mnt)2]? anions (A) form mixed stacks in …AACCAACC… fashion, and the neighboring mixed stacks are held together via van der Waals forces in the crystal. Compound 1 shows weak Curie/Weiss-type magnetic behavior from 2 to 370?K; theoretical investigation disclosed the existence of strongly antiferromagnetic coupling in both [Pd(mnt)2]2 2? and [TTF]2 2+ dimer pairs via frontier orbitals overlap mechanism and weakly ferromagnetic coupling between the face-to-face overlapped [TTF]+ and [Pd(mnt)2]? via spin polarization mechanism within a mixed stack. The powdered pellet electrical conductivity measurement indicated that 1 shows semiconductor character with activation energy of 1.1(3)?eV.  相似文献   

18.
New [M(R(2)pipdt)(2)](BF(4))(2) salts [R(2)pipdt = N,N'-dialkyl-piperazine-2,3-dithione; M = Pd(II), R = Me and M = Pt(II), R = Me, Et, Pr(i)] bearing redox-active cationic dithiolene complexes have been prepared and characterized. These cations react with the redox-active [M(mnt)(2)](2-) [M = Pd(II), Pt(II); mnt = maleonitrile-2,3-dithiolate] anionic dithiolenes to form salts describable as ion pair charge-transfer complexes. X-ray crystallographic studies have shown that [M(Me(2)pipdt)(2)][M(mnt)(2)] complexes, with M = Pd(II) and Pt(II), are isomorphous. Crystal data of the Pt salt (3a): triclinic, Ponemacr; (No. 2); Z = 1; T = 293(2) K; a = 6.784(7) A, b = 8.460(6) A, c = 13.510(5) A, alpha = 100.63(2) degrees, beta = 104.04(2) degrees, gamma = 96.90(2) degrees; R1 = 0.0691 [wR2 = 0.2187 (all data)]. Structural data show that approximately square-planar [Pt(Me(2)pipdt)(2)] dications and regular square-planar [Pt(mnt)(2)] dianions form an infinite anion-cation one-dimensional stack along axis a with a Pt...Pt a/2 distance of 3.392 A and a Pt...Pt...Pt angle of 180 degrees. Anions and cations arrange themselves face-to-face so as to take on a staggered arrangement. These salts exhibit strong absorptions in the visible-near-infrared region assigned to ion pair charge-transfer transitions. A relation between the optical and thermal electron transfer in the solid state is obtained using a "Marcus-Hush model", and a solid-state electrical conductivity in agreement with expectations is observed. Vibrational spectroscopy is in agreement with the existence of charge-transfer interactions between the cationic and anionic components of the salts.  相似文献   

19.
Three newly prepared [Ni(mnt)2] complexes, (HMTTF)[Ni(mnt)2], (ChSTF)[Ni(mnt)2], and (DBTTF)2[Ni(mnt)2], are reported (DBTTF = dibenzotetrathiafulvalene, ChSTF = 2,3-cyclohexylenedithio-1,4-dithia-5,8-diselanafulvalene, HMTTF = bis(trimethylene)-tetrathiafulvalene, and mnt = maleonitrile dithiolate). The former two compounds have usual DA-type (D = donor, A = acceptor) mixed stacks, whereas the DBTTF complex has DDDDAA-type 6-fold columns. These compounds are electrical insulators, but the HMTTF and ChSTF complexes exhibit chiT minima at 16 and 55 K, respectively, followed by chiT peaks at 8 and 16 K. Below these temperatures the ESR signal disappears, indicating antiferromagnetic transitions. The origin of the ferromagnetic interaction is explained either from the difference of the g values between the donor and the anion or from the intrinsic ferromagnetic interaction of the [Ni(mnt)2] anions.  相似文献   

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