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1.
Solid gold(I) fluoride remains as an unsynthesized and uncharacterized compound. We have performed a search for potential gold(I) fluoride crystal structures using USPEX evolutionary algorithm and dispersion-corrected hybrid density functional methods. Over 4000 AuF crystal structures have been investigated. Behavior of the AuF crystal structures under pressure was studied up to 25 GPa, and we also evaluated the thermodynamic stability of the hypothetical AuF crystal structures with respect to AuF3, AuF5, and Au3F8. Mixed-valence compound Au3[AuF4] with Au atoms in various formal oxidation states emerged as the thermodynamically most stable AuF species.  相似文献   

2.
The reaction of dinuclear copper(II ) cryptates with calcium cyanamide, CaNCN, and sodium dicyanamide, Na[N(CN)2] results in dinuclear compounds of formulae [Cu2(HNCN)(R3Bm)](ClO4)3 ( 1 ), [Cu2(dca)(R3Bm)](ClO4)3?4H2O ( 2 ), and [Cu2(NCNCONH2)(R3Bm)](CF3SO3)3 ( 3 ), in which R3Bm=N[(CH2)2NHCH2(C6H4m)CH2NH(CH2)2]3N and dca=dicyanamido ligand (NCNCN?). The X‐ray diffraction analysis reveals for both 1 and 3 a dinuclear entity in which the copper atoms are bridged by means of the ‐NCN‐ unit. The molar magnetic susceptibility measurements of 1–3 in the 2–300 K range indicate ferromagnetic coupling. The calculated J values, by using theoretical methods based on density functional theory (DFT) are in excellent agreement with the experimental data. Catalytic hydration of a nitrile to an amide functional group is assumed responsible for the formation of 3 from a μ1,3‐dicyanamido ligand.  相似文献   

3.
Our attempts to synthesize the hitherto unknown binary copper(I) fluoride have led to first successes and a serendipitious result: By conproportionation of elemental copper and copper(II) fluoride in anhydrous liquid ammonia, two copper(I) fluorides were obtained as simple NH3 complexes. One of them presents an example of ligand‐unsupported “cuprophilic” interactions in an infinite [Cu2(NH3)4]2+ chain with alternating Cu–Cu distances. We discovered that both copper(I) fluorides can easily be converted into Cu3N at room temperature, just by applying a vacuum. Additionally, we investigated the formation mechanism of the classical synthesis route of Cu3N that starts with CuF2 and flowing NH3 in the temperature range between ambient and 290 °C by means of thermal analysis and in situ neutron diffraction. The reaction proceeds at elevated temperatures through the formation of a blue and amorphous ammoniate Cu(NH3)2F2, the reformation of CuF2, and finally the redox reaction to form Cu3N.  相似文献   

4.
本文合成了1个新的铜双核配合物[(CuI)(PMN)]2.2CH3CN(PMN=2、4-二氨基-5-氯苯基-6-乙基嘧啶),并且通过元素分析、红外、荧光、热重和单晶X-射线进行了表征。该配合物属三斜晶系,空间群P1,a=0.8100(16)nm,b=0.96950(19)nm,c=1.2049(2)nm,α=97.88(3)°,β=93.31(3)°,γ=94.14(3)°,V=0.933 8(3)nm3,Z=1,R=0.037 1。在配合物中,每个Cu(Ⅰ)离子与PMN配体的1个N原子和2个I原子配位,展示出三角几何构型。相邻的2个Cu(Ⅰ)离子通过碘原子相连形成双核铜配合物,并进一步通过氢键和I…I作用形成三维网状结构。  相似文献   

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Trifluoromethylation of higher fullerene mixtures with CF3I was performed in ampoules at 400 to 420 and 550 to 560 °C. HPLC separation followed by crystal growth and X‐ray diffraction studies allowed the structure elucidation of nine CF3 derivatives of D2‐C84 (isomer 22). Molecular structures of two isomers of C84(22)(CF3)12, two isomers of C84(22)(CF3)14, four isomers of C84(22)(CF3)16, and one isomer of C84(22)(CF3)20 were discussed in terms of their addition patterns and relative formation energies. DFT calculations were also used to predict the most stable molecular structures of lower CF3 derivatives, C84(22)(CF3)2–10. It was found that the addition of CF3 groups to C84(22) is governed by two rules: additions can only occur at para positions of C6(CF3)2 hexagons and no additions can occur at triple‐hexagon‐junction positions on the fullerene cage.  相似文献   

7.
Trifluoromethylation of a higher fullerene mixture with CF3I was performed in ampoules at 550 °C. HPLC separation followed by crystal growth and X‐ray diffraction study resulted in the structure elucidation of nine CF3 derivatives of D2d‐C84 (isomer 23). The molecular structures of C84(23)(CF3)4, C84(23)(CF3)8, C84(23)(CF3)10, C84(23)(CF3)12, two isomers of C84(23)(CF3)14, two isomers of C84(23)(CF3)16, and C84(23)(CF3)18 were discussed in terms of their addition patterns and the relative formation energies. Extensive theoretical DFT calculations were performed to identify the most stable molecular structures. It was found that the addition of CF3 groups to the C84(23) fullerene is governed by two main rules: no additions in positions of triple hexagon junctions and predominantly para additions in C6(CF3)2 hexagons on the fullerene cage. The only exception with an isolated CF3 group in C84(23)(CF3)12 is discussed in more detail.  相似文献   

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The new barium nitridoosmate oxide (Ba6O)(OsN3)2 was prepared by reacting elemental barium and osmium (3:1) in nitrogen at 815–830 °C. The crystal structure of (Ba6O)(OsN3)2 as determined by laboratory powder X‐ray diffraction ( , No 148: a=b=8.112(1) Å, c=17.390(1) Å, V=991.0(1) Å3, Z=3), consists of sheets of trigonal OsN3 units and trigonal‐antiprismatic Ba6O groups, and is structurally related to the “313 nitrides” AE3MN3 (AE=Ca, Sr, Ba, M=V–Co, Ga). Density functional calculations, using a hybrid functional, likewise indicate the existence of oxygen in the Ba6 polyhedra. The oxidation state 4+ of osmium is confirmed, both by the calculations and by XPS measurements. The bonding properties of the OsN35? units are analyzed and compared to the Raman spectrum. The compound is paramagnetic from room temperature down to T=10 K. Between room temperature and 100 K it obeys the Curie–Weiss law (μ=1.68 μB). (Ba6O)(OsN3)2 is semiconducting with a good electronic conductivity at room temperature (8.74×10?2 Ω?1 cm?1). Below 142 K the temperature dependence of the conductivity resembles that of a variable‐range hopping mechanism.  相似文献   

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The haloacyltris(trifluoromethyl)borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been synthesized by reacting (CF3)3BCO with either MHal (M=K, Cs; Hal=F) in SO2 or MHal (M=[nBu4N]+, [Et4N]+, [Ph4P]+; Hal=Cl, Br, I) in dichloromethane. Metathesis reactions of the fluoroacyl complex with Me3SiHal (Hal=Cl, Br, I) led to the formation of its higher homologues. The thermal stabilities of the haloacyltris(trifluoromethyl)borates decrease from the fluorine to the iodine derivative. The chemical reactivities decrease in the same order as demonstrated by a series of selected reactions. The new [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br) salts are used as starting materials in the syntheses of novel compounds that contain the (CF3)3B-C fragment. All borate anions [(CF3)3BC(O)Hal]- (Hal=F, Cl, Br, I) have been characterized by multinuclear NMR spectroscopy (11B, 13C, 17O, 19F) and vibrational spectroscopy. [PPh4][(CF3)3BC(O)Br] crystallizes in the monoclinic space group P2/c (no. 13) and the bond parameters are compared with those of (CF3)3BCO and K[(CF3)3BC(O)F]. The interpretation of the spectroscopic and structural data are supported by DFT calculations [B3LYP/6-311+G(d)].  相似文献   

13.
0IntroductionThestudyofcopper?complexesisinvestigatedinmanylaboratories.Amongthereasonsforcarryingouttheinvestigationofsuchspeciesaretheirstructuralfeatures犤1犦,theusefulnessofcopper?compoundsinorganicsyntheses犤2犦andthewell-documentedimpor-tanceofcopper?centersattheactivesitesofanumberofprotein犤3犦.Concerningcopper?carboxy-latesafurtherinterestexists,stemmingfromtheiruseinhomogeheouscatalysedhydrogenation犤4犦.Thecopper?bis(triphenylphosphine)cationisasoft,butflexi-bleacceptorionthatcanacc…  相似文献   

14.
Cu2I2(PPh3)3·MDF(Ph=C6H5,DMF=HCON(CH3)2是通过W2S4(S2CN-(CH2CH2OH)2)2,PPh3和CuI在CH2Cl2和DMF为溶剂,在室温条件下合成的晶体产物。其窨群为P21/C,晶胞参数:C57H52Cu2I2NOP3,α=15.863(5),b=19.619(7),c=18.232(4),A,β=109.53(2)°,V=5348(3)A^3,Z=  相似文献   

15.
1INTRODUCT1oNIthasbeenwellknownthatthereactionofcopper(E)saltswithditertiaryphosphinesorarsinesisoftenaconvenientroutetocopper(I)analogues.8-dimethylarsinoquinolinee,3-methylthiopropyldimethylarsineand(o-diphenylarsi-nophenyl)diphenylphosphinesulphideallonlyyieldcopper(I)complexesofthiskindofligandsfromreactioninvolvingcopper(I)salts.Insimilarmanner,copper(I)nitratecomplexesofstoichiometryCu(dppm)(NO,),Cu2(dppe)3(NO,)2,Cu-(dppe),(NO,),andCu(dppe)(NO,)havebeenprepared.ltappearsthatthe…  相似文献   

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A new Bi? Li porphyrin sandwich compound, LiBi(TPP)2 has been synthesized and characterized (TPP=tetraphenylporphyrin). The unique molecular structure of LiBi(TPP)2 is such that the Bi sits between the porphyrins and is directed towards the Li. This complex was shown to remain intact in solution by temperature‐dependent 2D NMR spectroscopy. In order to investigate the potential interaction between these two metals, DFT calculations were used and showed a Bi 6s orbital polarized towards Li which could be indicative of a Bi? Li dative bond. This bond is remarkably short, 2.87 Å, and is among the shortest Bi? Li distances seen in a small molecule.  相似文献   

18.
PreparationandCrystalStructureofBis(2-thenoyltrifluoroacetone)Copper(Ⅱ)WangDong-Mei;YangRui-Na;HuYi-Min;JinDou-Man(HenanInsti...  相似文献   

19.
铜(I)配合物的研究在金属酶的化学模拟和配合物结构及反应性能等研究方面具有重要的理论和实际意义[1]。但由于铜(I)配合物不稳定,且在多数有机溶剂中的溶解度较小,铜(I)配合物的合成比较困难。我们在铜(I)配合物的合成方面积累了一些经验,合成了一系列含有三苯基膦和氮杂环配体的铜(I)配合物[CuX(PPh3)L]n[2~4](n=1,X=I,L=1,10phen;n=2,X=Br,I,L=C9H7N),并对它们的结构进行了研究。本文报道一个类似的新配合物[CuI(PPh3)(bpy)](I)的合成…  相似文献   

20.
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