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1.
New Phosphido-bridged Multinuclear Complexes of Ag and Zn. The Crystal Structures of [Ag3(PPh2)3(PnBu2tBu)3], [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2, PnPr3), [Ag4(PPh2)4(PEt3)4]n, [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2, PnBu3, PEt2Ph), [Zn4(PhPSiMe3)4Cl4(C4H8O)2] and [Zn4(PtBu2)4Cl4] AgCl reacts with Ph2PSiMe3 in the presence of tertiary Phosphines (PnBu2tBu, PMenPr2, PnPr3 and PEt3) to form the multinuclear complexes [Ag3(PPh2)3(PnBu2tBu)3] 1 , [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2 2 , PnPr3 3 ) and [Ag4(PPh2)4(PEt3)4]n 4 . In analogy to that ZnCl2 reacts with Ph2PSiMe3 and PRR′2 to form the multinuclear complexes [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2 5 , PnBu3 6 , PEt2Ph 7 ). Further it was possible to obtain the compounds [Zn4(PhPSiMe3)4Cl4(C4H8O)2] 8 and [Zn4(PtBu2)4Cl4] 9 by reaction of ZnCl2 with PhP(SiMe3)2 and tBu2PSiMe3, respectively. The structures were characterized by X-ray single crystal structure analysis. Crystallographic data see “Inhaltsübersicht”.  相似文献   

2.
Reaction of [UO2Cl2(THF)3] with 3 equivalents of LiC6Cl5 in Et2O resulted in the formation of first uranyl aryl complex [Li(Et2O)2(THF)][UO2(C6Cl5)3] ([Li][ 1 ]) in good yields. Subsequent dissolution of [Li][ 1 ] in THF resulted in conversion into [Li(THF)4][UO2(C6Cl5)3(THF)] ([Li][ 2 ]), also in good yields. DFT calculations reveal that the U−C bonds in [Li][ 1 ] and [Li][ 2 ] exhibit appreciable covalency. Additionally, the 13C NMR chemical shifts for their Cipso environments are strongly affected by spin-orbit coupling—a consequence of 5f orbital participation in the U−C bonds.  相似文献   

3.
Mononitrosyl and trans ‐Dinitrosyl Complexes of Phthalocyaninates of Manganese and Rhenium Tetra(n‐butyl)ammonium or di(triphenylphosphane)iminium nitrosylacidophthalocyaninato(2–)manganate, (cat)[Mn(NO)(X)pc2–] (X = ONO, NCO, N3; cat = nBu4N, PNP) is prepared from acidophthalocyaninato(2–)manganese, [Mn(X)pc2–], (cat)NO2 and (nBu4N)BH4 in CH2Cl2 or from nitrosylphthalocyaninato(2–)manganese, [Mn(NO)pc2–] and (nBu4N)X (X = ONO, NCO, N3, NCS) at T < 120 °C, respectively. [Mn(NO)(X)pc2–] dissociates in methanol, and [Mn(NO)pc2–] precipitates. Nitrito(O)phthalocyaninato(2–)manganese, (cat)NO2 and hydrogensulfide yield trans‐di(nitrosyl)phthalocyaninato(2–)manganate, trans[Mn(NO)2pc2–], isolated as red violet (PNP) and (nBu4N) complex salt. Nitrosyl(triphenylphosphane oxide)phthalocyaninato(2–)manganese, [Mn(NO)(OPPh3)pc2–] is obtained by addition of OPPh3 to [Mn(NO)pc2–] at 200 °C. Di(triphenylphosphane)phthalocyaninato(2–)rhenium(II) and (PNP)NO2 in CH2Cl2 or in molten (PNP)NO2 and PPh3 at 100 °C yields green blue l‐di(triphenylphosphane)iminium nitrosylnitrito(O)phthalocyaninato(2–)rhenate, l(PNP)[Re(NO)(ONO)pc2–]. Similarly, but with (nBu4N)NO2 red plates of tetra‐(n‐butyl)ammonium trans‐di(nitrosyl)phthalocyaninato(2–)rhenate, (nBu4N)trans[Re(NO)2pc2–] is isolated. Addition of (PNP)Br or (PNP)PF6 to a concentrated solution of (nBu4N)trans[Re(NO)2pc2–] in pyridine precipitates l(PNP)trans[Re(NO)2pc2–]. (nBu4N)trans[Re(NO)2pc2–] and PPh3 at 300 °C yield blue green nitrosyl(triphenylphosphane oxide)phthalocyaninato(2–)‐ rhenium, [Re(NO)(OPPh3)pc2–], that is oxidised with iodine precipitating nitrosyl(triphenylphosphane oxide)phthalocyaninato(2–)rhenium triiodide, [Re(NO)(OPPh3)pc2–]I3. The crystal structures of l(PNP)[Mn(NO)(ONO)pc2–] ( 1 ), l(PNP)‐ [Mn(NO)(NCO)pc2–] ( 2 ), l(PNP)trans[Mn(NO)2pc2–] ( 3 ), l(PNP)trans[Re(NO)2pc2–] ( 4 ) [Mn(NO)(OPPh3)pc2–] ( 5 ), [Re(NO)(OPPh3)pc2–] ( 6 ), and [Re(NO)(OPPh3)pc2–]I3 · CH2Cl2 ( 7 ) have been determined. The M–N(NO) distance varies between 1.623(12) Å in 5 and 1.846(3) Å in 3 . The M–N–O moiety is almost linear. The UV‐Vis spectra with the B band at ca. 14500 cm–1and the Q band at 30400 cm–1 do not dependent significantly on the axial ligand and the metal atom and its oxidation state. N–O stretching vibrations are observed in the IR spectra between 1701 cm–1 in 3 and 1753 cm–1 in [Mn(NO)pc2–] or for the Re series between 1571 cm–1 in 4 and 1724 cm–1 in 7 . M–N(NO) stretching and M–N–O deformation vibrations are assigned in the IR spectra and resonance Raman spectra between 486 cm–1 in 4 and 620 cm–1 in 1 .  相似文献   

4.
Syntheses and NMR Spectroscopic Ivestigations of Salts containing the Novel Anions [PtXn(CF3)6‐n]2— (n = 0 ‐ 5, X = F, OH, Cl, CN) and Crystal Structure of K2[(CF3)2F2Pt(μ‐OH)2PtF2(CF3)2]·2H2O The first syntheses of trifluoromethyl‐complexes of platinum through fluorination of cyanoplatinates are reported. The fluorination of tetracyanoplatinates(II), K2[Pt(CN)4], and hexacyanoplatinates(IV), K2[Pt(CN)6], with ClF in anhydrous HF leads after working up of the products to K2[(CF3)2F2Pt(μ‐OH)2PtF2(CF3)2]·2H2O. The structure of the salt is determined by a X‐ray structure analysis, P21/c (Nr. 14), a = 11.391(2), b = 11.565(2), c = 13.391(3)Å, β = 90.32(3)°, Z = 4, R1 = 0.0326 (I > 2σ(I)). The reaction of [Bu4N]2[Pt(CN)4] with ClF in CH2Cl2 generates mainly cis‐[Bu4N]2[PtCl2(CF3)4] and fac‐[Bu4N]2[PtCl3(CF3)3], but in contrast that of [Bu4N]2[Pt(CN)6] with ClF in CH2Cl2 results cis‐[Bu4N]2[PtX2(CF3)4], [Bu4N]2[PtX(CF3)5] (X = F, Cl) and [Bu4N]2[Pt(CF3)6]. In the products [Bu4N]2[PtXn(CF3)6‐n] (X = F, Cl, n = 0—3) it is possibel to exchange the fluoro‐ligands into chloro‐ and cyano‐ligands by treatment with (CH3)3SiCl und (CH3)3SiCN at 50 °C. With continuing warming the trifluoromethyl‐ligands are exchanged by chloro‐ and cyano‐ligands, while as intermediates CF2Cl and CF2CN ligands are formed. The identity of the new trifluoromethyl‐platinates is proved by 195Pt‐ and 19F‐NMR‐spectroscopy.  相似文献   

5.
Synthesis, Crystal Structures, and Vibrational Spectra of [Pt(N3)6]2– and [Pt(N3)Cl5]2–, 195Pt and 15N NMR Spectra of [Pt(N3)nCl6–n]2– and [Pt(15NN2)n(N215N)6–n]2–, n = 0–6 By ligand exchange of [PtCl6]2– with sodium azide mixed complexes of the series [Pt(N3)nCl6–n]2– and with 15N‐labelled sodium azide (Na15NN2) mixtures of the isotopomeres [Pt(15NN2)n(N215N)6–n]2–, n = 0–6 and the pair [Pt(15NN2)Cl5]2–/[Pt(N215N)Cl5]2– are formed. X‐ray structure determinations on single crystals of (Ph4P)2[Pt(N3)6] ( 1 ) (triclinic, space group P1, a = 10.175(1), b = 10.516(1), c = 12.380(2) Å, α = 87.822(9), β = 73.822(9), γ = 67.987(8)°, Z = 1) and (Ph4As)2[Pt(N3)Cl5] · HCON(CH3)2 ( 2 ) (triclinic, space group P1, a = 10.068(2), b = 11.001(2), c = 23.658(5) Å, α = 101.196(14), β = 93.977(15), γ = 101.484(13)°, Z = 2) have been performed. The bond lengths are Pt–N = 2.088 ( 1 ), 2.105 ( 2 ) and Pt–Cl = 2.318 Å ( 2 ). The approximate linear azido ligands with Nα–Nβ–Nγ‐angles = 173.5–174.6° are bonded with Pt–Nα–Nβ‐angles = 116.4–121.0°. In the vibrational spectra the PtCl stretching vibrations of (n‐Bu4N)2[Pt(N3)Cl5] are observed at 318–345, the PtN stretching modes of (n‐Bu4N)2[Pt(N3)6] at 401–428 and of (n‐Bu4N)2[Pt(N3)Cl5] at 408–413 cm–1. The mixtures (n‐Bu4N)2[Pt(15NN2)n(N215N)6–n], n = 0–6 and (n‐Bu4N)2[Pt(15NN2)Cl5]/(n‐Bu4N)2[Pt(N215N)Cl5] exhibit 15N‐isotopic shifts up to 20 cm–1. Based on the molecular parameters of the X‐ray determinations the vibrational spectra are assigned by normal coordinate analysis. The average valence force constants are fd(PtCl) = 1.93, fd(PtNα) = 2.38 and fd(NαNβ, NβNγ) = 12.39 mdyn/Å. In the 195Pt NMR spectrum of [Pt(N3)nCl6–n]2–, n = 0–6 downfield shifts with the increasing number of azido ligands are observed in the range 4766–5067 ppm. The 15N NMR spectrum of (n‐Bu4N)2[Pt(15NN2)n(N215N)6–n], n = 0–6 exhibits by 15N–195Pt coupling a pseudotriplett at –307.5 ppm. Due to the isotopomeres n = 0–5 for terminal 15N six well‐resolved signals with distances of 0.03 ppm are observed in the low field region at –201 to –199 ppm.  相似文献   

6.
Acetylpyridine thiosemicarbazone, HAPTSC ( 1 ), reacts with uranyl nitrate in MeOH under formation of (H2APTSC)[UO2(NO3)2(μ‐OH)]2 ( 2 ) or [ UO2(APTSC)(MeOH)(MeO)]2 ( 3 ) depending on the experimental conditions applied. Protonation of 1 and precipitation of the [UO2(NO3)2(μ‐OH)]22— dianion as acetylpyridinium thiosemicarbazone salt is observed when the reaction is performed without the addition of a base. The metal atoms are situated in the centres of distorted hexagonal bipyramids. The U—U distance is 3.892(1)Å. Addition of triethylamine results in deprotonation of HAPTSC and the formation of 3 which is an unusual dimer with four methanol/methanolato ligands of two metal sites sharing two protons. The U—U distance in this dimer is 5.313(1)Å. (Bu4N)[UO(APTSC)Cl2] ( 4 ) is obtained when (Bu4N)2[UO2Cl4] is used as precursor. The uranium atoms in 3 and 4 are seven co‐ordinate. Their co‐ordination polyhedra can best be described as pentagonal bipyramids. Compounds 3 and 4 represent the first examples of thiosemicarbazone complexes with actinide elements which haven been studied by X‐ray analysis.  相似文献   

7.

Crystal structure determinations on the uranyl ion complexes [H2N(CH3)2]2[UO2(bpdc)2], (1), (bpdc?=?2,2′-bipyridine-3,3′-dicarboxylate), [pyH]2[UO2(btfac)(NO3)2](NO3), (2), (btfac?=?1-phenyl-4,4,4-trifluorobutane-1,3-dionate), [H2dabco][UO2(nta)]2·3H2O, (3), (dabco?=?1,4-diazabicyclo[2.2.2]octane; nta?=?nitrilotriacetate) and [Ni(cyclam)UO2(edta)].2H2O, (4), (cyclam?=?1,4,8,11-tetrazacyclotetradecane; edta?=?ethylenediaminetetraacetate) have provided further examples of U(VI) in tetragonal-, pentagonal and hexagonal-bipyramidal coordination environments. Consideration of each structure within the context of those of known relatives has been used to assess the influence of factors in addition to repulsions within the primary coordination sphere on the equatorial coordination number of U(VI).

  相似文献   

8.
The state of ruthenium in conjugated phases upon extraction of trans-[Ru(15NO)(15NO2)4(OH)]2? complex with tri-n-octylphosphine oxide (TOPO) in the presence of Zn2+ and subsequent back extraction with H15NO3 and NH3(concd.) solutions was studied by 15N NMR. Binuclear complexes [Ru(NO)(NO2)5?n (μ-NO2) n?1(μ-OH)Zn(TOPO) n ] and [Ru(NO)(NO2)4?n (ONO)(μ-NO2) n?1(μ-OH)Zn(TOPO) n ], where n = 2, 3, are predominant forms in extract. Kinetic restrictions for ruthenium extraction with TOPO solution in hexane and its back extraction with aqueous solutions of nitric acid and ammonia are eliminated in the absence of direct coordination of extractant to ruthenium. fac-Dinitronitrosyl forms [Ru(NO)(H2O)3(NO2)2]+, [Ru(NO)(H2O)2(NO2)2(NO3)]0 (3 and 6 M HNO3) and [Ru(NO)(H2O)(NO2)2(NO3)2]? (6 M HNO3) prevail in nitric acid back extracts. Equilibrium constant at ambient temperature (0.05 ± 0.01) was assessed for the coordination of second nitrate ion to nitrosylruthenium dinitronitrato complex. Complex species [Ru(NO)(NO2)4(OH)]2? and [Ru(NO)(NO2)3(ONO)(OH)]2? prevail in ammonia back extract.  相似文献   

9.
We developed a hydrodehalogenation reaction of polyhaloalkanes catalyzed by paddlewheel dimolybdenum complexes in combination with 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene (MBTCD) as a non-toxic H-atom source as well as a salt-free reductant. A mixed-ligated dimolybdenum complex Mo2(OAc)2[CH(NAr)2]2 (3a, Ar = 4-MeOC6H4) having two acetates and two amidinates exhibited high catalytic activity in the presence of nBu4NCl, in which [nBu4N]2[Mo2{CH(NAr)2}2Cl4] (9a), derived by treating 3a with ClSiMe3 and nBu4NCl, was generated as a catalytically-active species in the hydrodehalogenation. All reaction processes, oxidation and reduction of the dimolybdenum complex, were clarified by control experiments, and the oxidized product, [nBu4N][Mo2{CH(NAr)2}2Cl4] (10a), was characterized by EPR and X-ray diffraction studies. Kinetic analysis of the hydrodehalogenation reaction as well as a deuterium-labelling experiment using MBTCD-d8 suggested that the H-abstraction was the rate-determining step for the catalytic reaction.  相似文献   

10.
Summary The reactions of [bipyH2][UO2Cl4]·3H2O (bipyH2=diprotonated 2,2-bipyridyl) with a series of neutral and protic oxygen donor ligands have been investigated. N,N-dimethyl formamide (DMF), N,N-dimethyl acetamide (DMA) and dimethyl sulphoxide (DMSO) gave compounds of the type [bipyH2][UO2Cl4(L)2] (L=DMF or DMA) and [bipyH2][UO2Cl4(DMSO)n] (DMSO)3-n (n=1 or 2), while [bipyH2][UO2Cl4-(3PNO)(DMSO)n](DMSO)2-n (n=1 or 2) and [bipyH][UO2Cl3(4PNO)(DMSO)] were obtained with 3-picoline N-oxide (3PNO) and 4-picoline N-oxide (4PNO) respectively from DMSO medium. With excess 2-picoline N-oxide (2PNO) the compound [bipyH][UO2Cl3(2PNO)](DMSO) was obtained. Reaction with acetyl acetone (AcAcH) and 8-hydroxy quinoline (QH) in 1:1 mole ratio in DMSO gave compounds of the type [bipyH2][UO2Cl3(L)(DMSO)] (L=AcAc or Q). The compounds have been investigated by i.r. spectra, powder x-ray diffraction and molar conductivity measurements.  相似文献   

11.
Syntheses and Crystal Structures of [Cu4(As4Ph4)2(PRR′2)4], [Cu14(AsPh)6(SCN)2(PEt2Ph)8], [Cu14(AsPh)6Cl2(PRR′2)8], [Cu12(AsPh)6(PPh3)6], [Cu10(AsPh)4Cl2(PMe3)8], [Cu12(AsSiMe3)6(PRR′2)6], and [Cu8(AsSiMe3)4(PtBu3)4] (R, R′ = Organic Groups) Through the reaction of CuSCN with AsPh(SiMe3)2 in the presence of tertiary phosphines the compounds [Cu4(As4Ph4)2(PRR′2)4] ( 1 – 3 ) ( 1 : R = R′ = nPr, 2 : R = R′ = Et; 3 : R = Me, R′ = nPr) and [Cu14(AsPh)6(SCN)2(PEt2Ph)8] ( 4 ) can be synthesised. Using CuCl instead of CuSCN results to the cluster complexes [Cu14(AsPh)6Cl2(PRR′2)8] ( 5–6 ) ( 5 : R = R′ = Et; 6 : R = Me, R′ = nPr), [Cu12(AsPh)6(PPh3)6] ( 7 ) and [Cu10(AsPh)4Cl2(PMe3)8] ( 8 ). Through reactions of CuOAc with As(SiMe3)3 in the presence of tertiary phosphines the compounds [Cu12(AsSiMe3)6(PRR′2)6] ( 9 – 11 ) ( 9 : R = R′ = Et; 10 : R = Ph, R′ = Et; 11 : R = Et, R′ = Ph) and [Cu8(AsSiMe3)4(PtBu3)4] ( 12 ) can be obtained. In each case the products were characterised by single‐crystal‐X‐ray‐structure‐analyses. As the main structure element 1 – 3 each have two As4Ph42–‐chains as ligands. In contrast 4 – 12 contain discrete AsR2–ligands.  相似文献   

12.
Complexes of the general formula HM(CO)n(oligophos) (M = V, n = 2; M = Nb, n = 3 and 2; M = Ta, n = 3) have been prepared by ion exchange on silica gel from their ionic precursors [Et4N][M(CO)4,3(oligophos)] (n = 3) or by UV irradiation of HM(CO)n+1(oligophos) (n = 2). The new compounds, including fac-[Et4N]-[Nb(CO)3PPh(CH2CH2PPh2)2] and cis-[Et4N][Ta(CO)4PPh(CH2CH2PPh2)2], are characterized by their IR (ν(CO)), 1H (hydride), 31P and metal (51V and 93Nb) NMR spectra.  相似文献   

13.
Coordination reactions of solutions of Re3Cl9 in acetonitrile, propanediol-1,2-carbonate, acetone and dimethylsulfoxide yield compounds with unchanged metal-cluster structures. The following compounds were isolated and characterised: [Et 4N]3[Re3Cl9(N3)3], [Et 4N]3[Re3Cl6(N3)6], [Et 4N]3[Re3Cl3(N3)9], [Et 4N]3[Re3Cl9(CN)3], [Et 4N]3[Re3Cl3(CN)9],Et 4N]3[Re3Cl9(NCS)3], [Et 4N]3[Re3Cl6(NCS)6], [Et 4N]3[Re3Cl3(NCS)9], Re3Cl9·(DMSO)3, Re3Cl9·(HMPT)3.  相似文献   

14.
Four new complexes of UO2(II) and Th(IV) with bis-Schiff bases, derived from N,N'-bis[(l-phenyl-3-methyl-5-oxo-4-pyrazolinyl)-a-furylmethylidyne]-1,2-propylenediimine [1,2-BPMOPFP-H2] and N,N'- bis[(l-phenyl-3-methyl-5-oxo-4-pyrazolinyl)-a-furylmethylidyne]-1,3-propylenediimine [1,3-BPMOPFP-H2], were synthesized and characterized by elemental analysis, IR, UV, 1HNMR spectroscopy, and molar conductivity. The general formula of the complexes was confirmed to be [UO2(BPMOPFP)], [Th(BPMOPFP)(NO3)]NO3. A possible structure for the complexes have been proposed.  相似文献   

15.
The synthesis of [TiInd(NCtBu2)Cl2] and the applications of [TiCp(NCtBu2)Cl2] (Cp=Ind, Cp*, Cp) as ethylene and propylene homopolymerisation catalysts, as well as its behaviour as catalysts of ethylene and 10-undecen-1-ol copolymerisation are described. The optimisation of the catalytic reactions showed that all compounds are very active homopolymerisation catalysts, particularly [TiInd(NCtBu2)Cl2] that gives 123.37 × 106 g/(molTi [E] h) and 50.77 × 106 g/(molTi [P] h) of linear polyethylene and atatic polypropylene, respectively. The less active homopolymerisation catalyst, [TiCp(NCtBu2)Cl2], is the most effective ethylene/10-undecen-1-ol copolymerisation catalyst, leading to the highest degree of polar monomer incorporation. The polymers obtained were characterised by NMR and DSC. The molecular structures of [TiCp(NCtBu2)Cl2] (Cp=Ind, Cp*) were determined by X-ray diffraction studies.  相似文献   

16.
The organophosphonate-substituted alkoxides [Bu4nN]2[{Ti(OMe)3(O3PPh)}2] (1) and [Bu4nN]2[{Nb(OMe)3(O3PPh)}2(μ-O)] (2) have been prepared from [Bu4nN][PhPO3H] and the metal alkoxides Ti(OMe)4 or Nb(OMe)5 respectively. In 1, the bridging phenylphosphonates occupy trans coordination sites, whereas in 2, a cis–bridging geometry is adopted.  相似文献   

17.
We report a phase diagram (on the mole fraction scale) for the [Th(NO3)4(TBP)2]-decane-[UO2(NO3)2(TBP)2](1-2-3) ternary liquid system, where TBP stands for tributyl phosphate, at T = 298.15 K. This system is characterized by a homogeneous solution field and a two-liquid field (immiscibility field); one phase (phase I) is enriched in [Th(NO3)4(TBP)2] and [UO2(NO3)2(TBP)2], and the other (phase II) is enriched in decane. Molecular interaction parameters and excess Gibbs energies G ex were calculated for the binary systems and the ternary liquid system along the binodal curve proceeding from miscibility in the [Th(NO3)4(TBP)2]-decane system and the ternary system and using equations of the NTRL model. For the ternary system, G ex > 0. G ex decreases in the following order of pairs of liquids: (1, 2) > (2, 3) > (1, 3).  相似文献   

18.
New tri-functional ligands of the type R2NCOCH2SCH2CONR2 (where R = iso-propyl, n-butyl or iso-butyl) were prepared and characterized. The coordination chemistry of these ligands with uranyl and lanthanum(III) nitrates was studied by using the IR, 1HNMR and elemental analysis methods. Structures for the compounds [UO2(NO3)2(iPr2NCOCH2SCH2CONiPr2)] [UO2(NO3)2(iBu2NCOCH2SCH2CONiBu2)], [La(NO3)3(iPr2NCOCH2SCH2CONiPr2)2] and [La(NO3)3(iBu2NCOCH2SCH2CONiBu2)2] were determined by single crystal X-ray diffraction. These structures show that the ligand acts as a bidentate chelating ligand and bonds through both the carbamoyl groups to the uranyl and lanthanum(III) nitrate groups. Solvent extraction studies show that the ligand can extract the uranyl ion from the nitric acid medium but does not show any ability to extract the americium (III) ion.  相似文献   

19.
Smart multifunctional molecular ferroelectrics bearing high Curie temperatures and diverse excellent physical properties, such as second harmonic generation (SHG) responses, luminescence, and semiconductivity, among others, have significant applications but have seldom been documented. Herein, the rare-earth metals Nd and Pr are introduced into a simple molecular system (nBu4N )3[M(NO3)x(SCN)y] (nBu4N=tetrabutyl ammonium, M=rare-earth metal, nBu=CH3CH2CH2CH2), and two new multifunctional molecular ferroelectrics are obtained: (nBu4N )3[Nd(NO3)4(SCN)2] ( 1 ) and (nBu4N )3[Pr(NO3)4(SCN)2] ( 2 ). Their distinct heat and dielectric anomaly dependence on temperature verifies that compounds 1 and 2 experience high-temperature para-ferroelectric phase transitions at 408 and 413 K, respectively. Strikingly, both molecular ferroelectrics possess large spontaneous polarization with Ps values of 9.05 and 8.50 μC cm−2, respectively, and are further characterized by the appearance of multiple intersecting non-180° domains and polarization switching behavior. In particular, compounds 1 and 2 show good stability with only a small decrease in SHG intensity after switching cycles, suggesting that they have great potential for application in nonlinear optical (NLO) switches. Simultaneously, the rare-earth compounds 1 and 2 present bright yellow–red and bright green fluorescence, respectively, at room temperature.  相似文献   

20.
The phase diagram of the ternary liquid system [Th(NO3)4(TBP)2]-[UO2(NO3)2(TBP)2]-tetradecane (where TBP stands for tri-n-butyl phosphate) has been investigated at temperatures from 298.15 to 333.15 K. The ternary liquid system is characterized by a region of homogeneous solutions and a region of two-phase liquid systems (stratified systems). One phase is enriched with solvates [Th(NO3)4(TBP)3] and [UO2(NO3)2(TBP)2] (phase I), and the other is enriched with tetradecane (phase II). The temperature (T = 298.15–333.15 K) does not substantially affect the two-phase region. In the two-phase systems, the preferential distribution of [UO2(NO3)2(TBP)2] into phase I is observed in spite of the fact that the binary system [UO2(NO3)2(TBP)2]-tetradecane is a single phase at all temperatures investigated. The distribution of [UO2(NO3)2(TBP)2] into phase I leads to the redistribution of [Th(NO3)4(TBP)2] into phase II. At all temperatures investigated, the critical solution points of the ternary liquid system have compositions with close contents of the solvates [Th(NO3)4(TBP)2] and [UO2(NO3)2(TBP)2].  相似文献   

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