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1.
A series of luminescent rhenium(I) monoynyl complexes, [Re(N---N)(CO) 3(CC---R)] (N---N=bpy, tBu 2bpy; R=C 6H 5, C 6H 4---Cl-4, C 6H 4---OCH 3-4, C 6H 4---C 8H 17-4, C 6H 4---C 6H 5, C 8H 17, C 4H 3S, C 4H 2S---C 4H 3S, C 5H 4N), together with their homo- and hetero-metallic binuclear complexes, {Re(N---N)(CO) 3(CC---C 5H 4N)[M]} (N---N=bpy, tBu 2bpy; [M]=[Re{(CF 3) 2-bpy}(CO) 3]ClO 4, [Re(NO 2-phen)(CO) 3]ClO 4, W(CO) 5) have been synthesized and their electrochemical and photoluminescence behaviors determined. The structural characterization and electronic structures of selected complexes have also been studied. The luminescence origin of the rhenium(I) alkynyl complexes has been assigned as derived states of a [dπ(Re)→π*(N---N)] metal-to-ligand charge transfer (MLCT) origin mixed with a [π(CCR)→π*(N---N)] ligand-to-ligand charge transfer (LLCT) character. The assignments are further supported by extended Hückel molecular orbital (EHMO) calculations, which show that the LUMO mainly consists of π*(N---N) character while the HOMO is dominated by the antibonding character of the Re---CCR moiety resulted from the overlap of the dπ(Re) and π(CCR) orbitals. 相似文献
2.
The title compounds react with unidentate ligands, L, containing either phosphorus or arsenic donor atoms to yield the corresponding compounds of the type Ru(η 5---C 5Me 4Et)(CO)LX; with didentate phosphorus donor ligands the major species formed is the bridged complex {Ru(η 5---C 5Me 4Et)(CO)X} 2{Ph 2P(CH 2) nPPh 2} n = 1, X = Br; n = 2, X = Cl). In contrast, unidentate ligands containing nitrogen donor atoms such as pyridine did not react with Ru(η 5---C 5Me 4Et)(CO) 2Cl although reaction with 1,10-phenanthroline or diethylenetriamine yielded the ionic products [Ru(η 5---C 5Me 4Et)(CO)L] +Cl − (L = phen or (NH 2CH 2CH 2) 2NH). Reaction of Ru(η 5---C 5Me 4Et)(CO) 2Br with AgOAc yielded the corresponding acetato complex Ru(η 5---C 5Me 4Et)(CO) 20Ac. Ru(η 5--- C 5Me 4Et)(CO) 2X reacts with AgY (Y = BF 4 or PF 6) in either acetone or dichloromethane to give the useful solvent intermediates [Ru(η 5---C 5Me 4Et)(CO) 2(solvent)] +Y −, which readily react with ligands L to yield ionic derivatives of the type [Ru(η 5---C 5Me 4Et)(CO) 2L] +Y − (where L = CO, NCMe, py, C 2H 4 or MeO 2CCCCO 2Me). 相似文献
3.
The new diphenolato complexes [{Mo(NO){HB(dmpz) 3}Cl} 2Q] where dmpz = 3,5-dimethylpyrazolyl and Q = OC 6H 4(C 6H 4O ( n = 1 or 2), OC 6H 4CR=CRC 6H 4O (R = H or Et), and OC 6H 4CH=CHC 6H 4CH=CHC 6H 4O have been prepared and their electrochemical properties (cyclic and differential pulse voltammetry) compared with previously reported analogues where Q = OC 6H 4O, OC 6H 4EC 6H 4O (E = SO 2, CO and S), OC 6H 4 (CO)C 6H 4 C 6H 4(CO)C 6H 4O and 1,5- and 2,7-O 2C 10H 6. The electrochemical interaction between the redox centres in the new complexes is very weak, in contrast to that in the 1,4-benzenediolato and naphthalendiolato species. The EPR spectra of the reduced mixed-valence species [{Mo(NO){HB(dmpz) 3}Cl} 2Q] − where Q = 1,3- and 1,4-OC 6H 4O and OC 6H 4SC 6H 4O shows that they are valence-trapped at room temperature, whereas those of the dianions [{Mo(NO){HB(dmpz) 3}Cl} 2Q] 2− where Q = 1,4-OC 6H 4O, OC 6H 4EC 6H 4O (E = CO or S) and OC 6H 4CH=CHC 6H 4CH=CHC 6H 4O shows that the unpaired spins on each molybdenum centre are strongly correlated ( J, the spin exchange integral A Mo, the metal-hyperfine coupling constant). The electrochemical properties and the comproportionation constants for the reaction [{Mo(NO){HB(dmpz) 3} Cl} 2Q] + [{Mo(NO){HB(dmpz) 3}Cl}O] 2] 2−2[{Mo(NO) {HB(dmpz) 3}Cl} 2Q] − where Q = diphenolato bridge, are compared with related compounds containing benzenediamido and dianilido bridges. 相似文献
4.
[1,8-C 10H 6(NR) 2]TiCl 2 (3; R=SiMe 3, Si iBuMe 2, Si iPr 3) complexes have been prepared from dilithio salts [1,8-C 10H 6(NR) 2]Li 2 (2) and TiCl 4 in diethyl ether in moderate yields (60–63%). These complexes showed significant catalytic activities for ethylene polymerization and for ethylene/1-hexene copolymerization in the presence of methylaluminoxane (MAO), methyl isobutyl aluminoxane (MMAO), Al iBu 3– or AlEt 3–Ph 3CB(C 6F 5) 4 as a cocatalyst. The catalytic activities performed in heptane (cocatalyst MMAO) were higher than those carried out in toluene (cocatalyst MAO): 709 kg-PE/mol-Ti·h could be attained for ethylene polymerization by using [1,8-C 10H 6(NSi iBuMe 2) 2]TiCl 2–MMAO catalyst system. 相似文献
5.
Two organogold derivatives of diphenylmethane and diphenylethane, Ph 3PAu( o-C 6H 4)CH 2(C 6H 4- o)AuPPh 3 (1) and Ph 3PAu( o-C 6H 4)(CH 2) 2(C 6H 4- o)AuPPh 3 (2), have been synthesized by the reaction of ClAuPPh 3 with Li( o-C 6H 4)CH 2(C 6H 4- o)Li and Li( o-C 6H 4)(CH 2) 2(C 6H 4- o)Li respectively. The interaction of 1 with dppe results in the replacement of the two PPh 3 groups to give a macrocyclic compound (3) that includes an Au Au bond. Compounds 1 and 2 react with one or two equivalents of [Ph 3PAu]BF 4 to form new types of cationic complex [CH 2(C 6H 4- o) 2(AuPPh 3) 3]BF 4 (4), [CH 2(C 6H 4- o) 2(AuPPh 3) 4](BF 4) 2 (5), and [(CH 2) 2(C 6H 4- o) 2(AuPPh 3) 4](BF 4) 2 (6). Complexes 1–6 have been characterized by X-ray diffraction studies, FAB MS, and IR as well as by 1H and 31P NMR spectroscopy. A complicated system of Au H-C agostic interactions, involving the bridging alkyl groups (—CH 2— and CH 2-CH 2—) of diphenylmethane and diphenylethane ligands, has been found to occur in complexes 1–3 and 6. 相似文献
6.
From the reaction of MeReO 3 with the neutral arylamine C 6H 5CH 2NMe 2 and the aryldiamine C 6H 4(CH 2NMe 2) 2−1,3, have been isolated in good yields the 1/1 adduct complex [MeReO 3 · C 6H 5CH 2NMe 2], 1, and the 2/1 adduct complex [(MeReO 3) 2 · C 6H 4(CH 2NMe 2) 2− 1,3], 2, respectively. The X-ray molecular structure of 2 shows that both rhenium centres have a trigonal bipyramidal geometry and in the axial positions of each rhenium centre are one of the NMe 2 units of the aryldiamine ligand and a methyl group. The mono(ortho)-chelated arylaminorhenium trioxide complex [ReO 3(C 6H 4CH 2NMe 2−2], 3, can be synthesized by a transmetallation reaction of ClReO 3 with [ZnC 6H 4CH 2NMe 2−2 2] in a 2:1 molar ratio. In a similar way the bis(ortho)-chelated arylaminorhenium trioxide complex [ReO 3C 6H 3(CH 2NMe 2) 2−2,6], 4, can be synthesized by addition of a mixture of [Li 2C 6H 3(CH 2NMe 2) 2−2,6 2] and ZnCl 2 to ClReO 3. Complexes 3 and 4 have been isolated as white solids in 66% and 81% yields respectively. The rhenium centre in complex 4 has a bicapped tetrahedral geometry in which the monoanionic C 6H 3(CH 2NMe 2) 2−2,6 − ligand is pseudo-facially bonded with a characteristic N1-Re-N2 angle of 107.7(3)°, a Re-C ipso bond length of 2.112(11) Å and Re-N1 and Re-N2 bond lengths of 2.518(9) Å and 2.480(8) Å respectively. 相似文献
7.
The azacyclopentadienyl compounds (2,5-C 4tBu 2RHN)MCl 3 (M = Ti, Zr, Hf; R = H, SiMe 3) have been prepared as stable solids from the lithiated pyrroles and MCl 4. The π-coordination of the azacyclopentadienyl ligands, as suggested from 13 C NMR data, has been confirmed for (2,5-C 4tBu 2H 2N)TiCl 3 by an X-ray diffraction study. 相似文献
8.
The directed oligomerization of propene and 1-hexene was carried out with a series of Cp′(C 5H 5)ZrCl 2 and Cp 2′ZrCl 2 pre-catalysts (Cp′=C 5HMe 4, C 4Me 4P, C 5Me 5, C 5H 4tBu, C 5H 3-1,3- tBu 2, C 5H 2-1,2,4- tBu 3) together with (C 5H 5) 2ZrCl 2. Oligomers in the molar mass range 300–1500 g/mol for propene and 200–3000 g/mol for 1-hexene were synthesized at 50 °C. The majority of oligomer molecules contain a double-bond end group. Oligomer characterization was carried out by gel permeation chromatography (GPC), 1H and 13C NMR. Vinylidene double bonds (from β-hydrogen elimination) are solely found for the tert-butyl-substituted zirconocenes and for most of the unsymmetrical methyl-substituted Cp′(C 5H 5)ZrCl 2 systems (except Cp′=phospholyl). With (C 4Me 4P)(C 5H 5)ZrCl 2 and with the symmetrical methyl-containing Cp 2′ZrCl 2 pre-catalysts, also vinyl end groups (from β-methyl elimination) are observed in the case of oligopropenes. The vinylidene/vinyl ratio depends on the ligand and the vinyl content increases from C 5HMe 4 (65/35) over C 4Me 4P (61/39) to C 5Me 5 (9/91). The phospholyl zirconocenes and (C 5HMe 4) 2ZrCl 2 also exhibit chain-transfer to aluminum thereby giving saturated oligomers. 相似文献
9.
Three families of heterobimetallic compounds were obtained by reaction of [Mo(CO) 3(CH 3CN) 2(Cl)(SnRCl 2)] (R = Ph, Me) with P(4-XC 6H 4) 3 (X = Cl, F, H, Me, MeO). The type of compound obtained dependent on the solvent and concentration of the starting compound. So, [Mo(CO) 2(CH 3COCH 3) 2(PPh 3)(Cl)(SnRCl 2)]· nCH 3COCH 3 (R = Ph, n = 0.5; R = Me, n = 1) (type I) and [Mo(CO) 3{P(4-XC 6H 4) 3}(μ-Cl)(SnRCl 2)] 2 (R = Ph, X = Cl, F, H, Me, MeO; R = Me, X = Cl, F) (type II) were isolated from acetone solution in ca 0.05 M and 0.1 M concentrations, respectively. However, [Mo(CO) 3(CH 3CN) {P(4-XC 6H 4) 3}(Cl)(SnRCl 2)] (R = Ph, X = H; R = Me, X = Cl, F, H) (type III) were obtained from dichloromethane solution independently of the concentration used. All new complexes showed a seven-coordinate environment at molybdenum, containing Mo---Cl and Mo---Sn bonds. Mössbauer spectra indicated a four-coordination at tin for type III complexes. 相似文献
10.
The complex [MoW(μ-CC 6H 4Me-4)(CO) 2(η 7-C 7H 7)(η 5-C 2B 9H 10Me)] reacts with diazomethane in Et 2O containing EtOH to afford the dimetal compound [MoW(OEt)(μ-CH 2){μ-C(C 6H 4Me-4)C(Me)O}(η 7-C 7H 7)(η 5-C 2B 9H 10Me)]. The structure of this product was established by X-ray diffraction. The Mo---W bond [2.778(4) Å] is bridged by a CH 2 group [μ-C---Mo 2.14(3), μ-C---W 2.02(3) Å] and by a C(C 6H 4Me-4)C(Me)O fragment [Mo---O 2.11(3), W---O 2.18(2), Mo---C(C 6H 4Me-4) 2.41(3), W---C(C 6H 4Me-4) 2.09(3), Mo---C(Me) 2.26(3) Å]. The molybdenum atom is η 7-coordinated by the C 7H 7 ring and the tungsten atom is η 5-coordinated by the open pentagonal face of the nido-icosahedral C 2B 9H 10Me cage. The tungsten atom also carries a terminally bound OEt group [W---O 1.88(3) Å]. The 1H and 13C-{ 1H} NMR data for the dimetal compound are reported and discussed. 相似文献
11.
Six new cluster derivatives [Rh 2Co 2(CO) 6(μ-CO) 4(μ 4,η 2-HCCR)] (R=FeCp 2 1, CH 2OH 2, (CH 3O)C 10H 6CH(CH 3)COOCH 2CCH 3) and [RhCo 3(CO) 6(μ-CO) 4(μ 4,η 2-HCCR)] (R=FeCp 2 4, CH 2OH 5, (CH 3O)C 10H 6CH(CH 3)COOCH 2CCH 6) were obtained by the reactions of [Rh 2Co 2(CO) 12] and [RhCo 3(CO) 12] with substituted 1-alkyne ligands HCCR [R=FeCp 2 7, CH 2OH 8, (CH 3O)C 10H 6CH(CH 3) COOCH 2CCH 9] in n-hexane at room temperature, respectively. Alkynes insert into the Co---Co bond of the tetranuclear clusters to give butterfly clusters. [Rh 2Co 2(CO) 6(μ-CO) 4(μ 4,η 2-HCCFeCp 2)] (1) was characterized by a single-crystal X-ray diffraction analysis. Reactions of 1, 2 with 7, 8 and ambient pressure of carbon monoxide at 25 °C gave two known cluster complexes [Co 2(CO) 6(μ 2, η 2-HCCR)] (R=FeCp 2 10, CH 2OH 11), respectively. All clusters were characterized by element analysis, IR and 1H-NMR spectroscopy. 相似文献
12.
Reduction of (C 5H 5) 2TiCl 2 with Zn in presence of benzyl cyanide gives the (μ-alkyl-ideneamido)titanocene complex [(C 5H 5) 2TiCl] 2[μ-{N=C(CH 2C 6H 5)---C(CH 2C 6H 5)=N}] with C---C bond formation between two benzyl cyanide molecules. X-ray structure investigation indicates a symmetrical structure. The C=N distances are smaller than usual, the Ti---N distances are very short, and the Ti---N---C angle differs only a little from 180°, which infers a heteroallene structure of the complex. 相似文献
13.
The ruthenium(II) complex Ru(CO) 2(NH 2(NH 2CH 2C 6H 5) 2(Si(C 6H 5)(CH 3) 2)I has been prepared by the reaction of Ru(CO) 4(Si(C 6H 5)(CH 3) 2)I with benzylamine. Two-dimensional homonuclear 1H NMR experiments examine the scalar coupling of the enantiotopic amino and methylene protons of the benzylamine ligand. X-ray analysis of Ru(CO) 2(NH 2CH 2C 6H 5) 2(Si(C 6H 5)(CH 3) 2)I·1/3C 5H 12 (triclinic; P
; a = 14.266(4), b = 15.748(5), c = 20.082(6) Å; = 94.38(3), β = 96.30(2), γ = 101.52(2)°) indicates three crystallographically unique complexes form a clathrate with a pentane guest. 相似文献
14.
采用自制的新型双苯并环己酮芳亚胺镍催化剂双苯并环己酮-2,6-二甲基苯亚胺镍(Ⅱ)(Ni{C 10H 8(O)C[2,6-C 6H 3(CH 3) 2N]CH 3} 2, C1)和双苯并环己酮-2,6-二氯苯亚胺镍(Ⅱ)(Ni{C 10H 8(O)C[2,6-C 6H 3Cl 2N]CH 3} 2, C2)与三五氟苯硼[B(C 6F 5) 3]结合, 在一定的反应条件下可高效催化降冰片烯(NB)与甲基丙烯酸正丁酯( n-BMA)的乙烯基加成共聚合. 提出了催化聚合时存在的可能失活机理; 研究了不同单体投料比对催化活性、 产率及产物性能的影响. 根据Kelen-Tüdõs方法分别估算出2种单体在不同催化体系下的竞聚率, 即当催化体系为C1/B(C 6F 5) 3时, 竞聚率 rn-BMA=0.02, rNB=16.28, rNB· rn-BMA=0.32; 当催化体系为C2/B(C 6F 5) 3时, rn-BMA=0.01, rNB=64.83, rNB· rn-BMA=0.65. 结果表明, 2种单体在2种体系催化下均为无规共聚合. 相似文献
15.
The effects of cyclopentadienyl ring size on the geometry of bimetallic organosamarium complexes have been studied by comparing the X-ray crystal structure of [(C 5H 4Me) 2(THF)Sm(μ-Cl)] 2, prepared from KC 5H 4Me and SmCl 3 in THF, with C 5Me 5 analogs. The complex crystallizes from THF at −30°C in space group Pbcn with a = 20.312(5), b = 9.626(2), c = 16.225(3) Å, V = 3172.5(12) Å 3 and Dcalc = 1.74 g cm −3 for Z = 4. Least-squares refinement of the model based on 1759 reflections [| Fo| > 2.0σ(| Fo|)] converged to a final RF = 5.0%. The complex adopts a geometry which has a molecular two-fold rotation axis perpendicular to the Sm 2Cl 2 plane and a crystallographic inversion center. Hence, both methyl groups of each (C 5H 4Me) 2Sm unit are located on the side opposite of the THF ligands, which are trans to each other, and the four C 5H 4Me ring centroids define a square plane. The Sm---Cl distances are 2.759(3) and 2.819(3) Å. 相似文献
16.
While each of the three organosamarium(III) title complexes: [Cp 2Sm{μ-OC 10H 19}] 2 (5; Cp = C 5H 5, OC 10H 19 = isomenthoxide), [Cp 2Sm{μ-OCH(Me)COO iBU}] 2 (6) and [Cp 3SmOS(Me)- p-C 6H 4Me] (7) contains a chiral ligand atom (i.e. C or S) next to the metal-bonded oxygen atoms, only the dinuclear compounds 5 and, even better, 6 display (below ca. 600 nm) significant circular dichroism of discrete f---f-crystal field transitions. According to a successful single-crystal X-ray study of 5, the cyclohexyl ring of its (1S,2R,5R)-isomenthoxide ligand adopts a conformation with axial OSm- and iPr-substituents, which is energetically less favourable at least for neat (1S,2R,5R)-isomenthol. ZusammenfassungObwohl jeder der drei neuen Organosamarium(III)-Komplexe: [Cp2Sm{μ-OC10OH19}]2 (5; Cp = C5H5, OC10H19 = Isomentholat), [Cp2Sm{μ-OCH(Me)COOiBU}]2 (6) und [Cp3SmOS(Me)-p-C6H4Me] mindestens ein chirales Ligandenatom (C oder S) unmittelbar am metallkoordinierten O-Atom enthält, zeigen nur die dimeren Systeme 5 und noch ausgeprägter 6 (unterhalb von ca. 600 nm) signifikanten Circulardichroismus von f---f-Kristallfeldübergängen des Sm3+-Ions. Auf Grund einer erfolgreichen Kristallstrukturanalyse von 5 liegt der Cyclohexylring des (1S,2R,5R)-Isomentholatliganden ausschließlich in der Konformation mit axialen OSm- und iPr-Substituenten vor, die für freies (1S,2R,5R)-Isomenthol energetisch deutlich unvorteilhafter ist. 相似文献
17.
利用Co 2(CO) 8与[Cl 3CC(O)OCH 2] 2的反应合成了以C(O)OCH 2CH 2OC(O)桥联两个Co 3C四面体骨架为特征的新型双四面体簇合物[(CO) 9Co 3(μ 3-C)C(O)OCH 2] 2(1);1与不同物质的量比的Na[M(CO) 3C 5H 4R](M=Mo,W;R=H,C(O)Me)反应,得到一步交换的产物(CO) 9Co 3(μ 3-C)C(O)OCH 2CH 2OC(O)(μ 3-C)Co 2M(CO) 8(C 5H 4R)[M=Mo,R=H(2);M=Mo,R=C(O)Me(3);M=W,R=H(4);M=W,R=C(O)Me(5)]或两步交换的产物[(C 5H 4R)(CO) 8Co 2M(μ 3-C)C(O)OCH 2] 2[M=Mo,R=H(6);M=Mo,R=C(O)Me(7);M=W,R=H(8);M=W,R=C(O)Me(9)].5或9分别与Na[Mo(CO) 3C 5H 5]以12的物质的量比反应得到含一个手性四面体骨架(CoMoWC)的(C 5H 5)(CO) 8Co 2Mo(μ 3-C)C(O)OCH 2CH 2O·C(O)(μ 3-C)CoMoW(CO) 7(C 5H 4C(O)Me)(C 5H 5)(10)或含两个手性四面体骨架(CoMoWC)的[(C 5H 5)(C 5H 4C(O)Me)(CO) 7CoMoW(μ 3-C)C(O)OCH 2] 2(11);对化合物1_11进行了CH元素分析、IR和 1HNMR等表征.结果表明,在金属交换反应中处于不同簇环境下的Co(CO) 3基团反应活性不同.对化合物1进行了晶体X射线衍射分析.化合物1的晶体属单斜晶系,P2 1/n(#14)空间群,晶胞参数a=0.933 0(2)nm,b=1.519 7(4)nm,c=1.178 3(4)nm,=91.16(2)°,Z=2,F(000)=972.分子结构呈中心对称. 相似文献
18.
IntroductionThe accidental discovery of ferrocene, (C,H,)ZFe, has been well recognized as a majorcause of the subsequent explosive growth of organometallic chemistry['--'1. Metallocenes havebecome the most famous organometallic compounds. Recently, a considerable attention hasbeen given to the study of the vibrational spectra of metallocenes and the complexes containingthe M-(f-C,H,) unit. The problems concerning the spectroscopy and the structure of cyclopentadienyl complexes have been dis… 相似文献
19.
The acid–base chemistry of some ruthenium ethyne-1,2-diyl complexes, [{Ru(CO) 2(η-C 5H 4R)} 2(μ 2-CC)] (R=H, Me) has been investigated. Initial protonation of [{Ru(CO) 2{η-C 5H 4R}} 2(μ 2-CC)] gave the unexpected complex cation, crystallised as the BF 4 salt, [{Ru(CO) 2(η-C 5H 4R}} 3(μ 3-CC)][BF 4] (R=Me structurally characterised). This synthesis proved to be unreliable but subsequent, careful protonation experiments gave excellent yields of the protonated ethyne-1,2-diyl complexes, [{Ru(CO) 2{η-C 5H 4R)} 2(μ 2-η 1:η 2-CCH)](BF 4) (R=Me structurally characterised) which could be deprotonated in high yield to return the starting ethyne-1,2-diyl complexes. 相似文献
20.
Thermal displacement of coordinated nitriles RCN (R = CH 3, C 2H 5 or n-C 3H 7) in [C 5H 5Fe(L 2)(NCR)]X complexes (L 2 = P(OCH 3) 3) 2, (P(OC 6H 5) 3) 2 or (C 6H 5) 2PC 2H 4P(C 6H 5) 2 (DPPE)) by E(CH 3) 2 affords high yields of [C 5H 5Fe(L 2)(E(CH 3) 2)]X compounds (E = S, Se and Te; X = BF 4 or PF 6). Spectroscopic data and ligand displacement reactions are presented and discussed together with related observations on [C 5H 5Fe(CO) 2(E(CH 3) 2)]BF 4 compounds. The molecular structure of [C 5H 5Fe(P(OCH 3) 3) 2(S(CH 3) 2)]PF 6 was determined by a single-crystal X-ray diffraction study: monoclinic, space group P2 1/ n- C52h (No. 14) with a = 8.4064(12), b = 11.183(2), c = 50.726(8) Å, β = 90.672(13)° and Z = 8 molecules per unit cell. The coordination sphere of the iron atom is pseudo-tetrahedral with an Fe---S bond distance of 2.238 Å. 相似文献
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