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1.
The reaction of Al, Ga, or In metals and H5IO6 in aqueous media at 180 °C leads to the formation of Al(IO3)3, Ga(IO3)3, or In(IO3)3, respectively. Single-crystal X-ray diffraction experiments have shown In(IO3)3 contains the Te4O9-type structure, while both Al(IO3)3 and Ga(IO3)3 are known to exhibit the polar Fe(IO3)3-type structure. Crystallographic data for In(IO3)3, trigonal, space group , a=9.7482(4) Å, c=14.1374(6) Å, V=1163.45(8) Z=6, R(F)=1.38% for 41 parameters with 644 reflections with I>2σ(I). All three iodate structures contain group 13 metal cations in a distorted octahedral coordination environment. M(IO3)3 (M=Al, Ga) contain a three-dimensional network formed by the bridging of Al3+ or Ga3+ cations by iodate anions. With In(IO3)3, iodate anions bridge In3+ cations in two-dimensional layers. Both materials contain distorted octahedral holes in their structures formed by terminal oxygen atoms from the iodate anions. The Raman spectra have been collected for these metal iodates; In(IO3)3 was found to display a distinctively different vibrational profile than Al(IO3)3 or Ga(IO3)3. Hence, the Raman profile can be used as a rapid diagnostic tool to discern between the different structural motifs.  相似文献   

2.
By replacing Mn in YCa3(MnO)3(BO3)4 with trivalent Al and Ga, two new borates with the compositions of YCa3(MO)3(BO3)4 (M=Al, Ga) were prepared by solid-state reaction. Structure refinements from X-ray powder diffraction data revealed that both of them are isostructural to gaudefroyite with a hexagonal space group P63/m. Cell parameters of a=10.38775(13)Å, c=5.69198(10)Å for the Al-containing compound and a=10.5167(3)Å, c=5.8146(2)Å for the Ga analog were obtained from the refinements. The structure is constituted of AlO6 or GaO6 octahedral chains interconnected by BO3 groups in the ab plane to form a Kagomé-type lattice, leaving trigonal and apatite-like tunnels. It is found that most rare-earth and Cr, Mn ions can be substituted into the Y3+ and M3+ sites, respectively, and the preference of rare-earth ions to locate in the trigonal tunnel is correlated to the sizes of the M3+ ions.  相似文献   

3.
A new ruthenium-rhodium mixed-metal cluster HRuRh3(CO)12 and its derivatives HRuRh3(CO)10(PPh3)2 and HRuCo3(CO)10(PPh3)2 have been synthesized and characterized. The following crystal and molecular structures are reported: HRuRh3(CO)12: monoclinic, space group P21/c, a 9.230(4), b 11.790(5), c 17.124(9) Å, β 91.29(4)°, Z = 4; HRuRh3(CO)10(PPh3)2·C6H14: triclinic, space group P1, a 11.777(2), b 14.079(2), c 17.010(2) Å, α 86.99(1), β 76.91(1), γ 72.49(1)°, Z = 2; HRuCo3(CO)10(PPh3)2·CH2Cl2: triclinic, space group P1, a 11.577(7), b 13.729(7), c 16.777(10) Å, α 81.39(4), β 77.84(5), γ 65.56°, Z = 2. The reaction between Rh(CO)4? and (Ru(CO)3Cl2)2 tetrahydrofuran followed by acid treatment yields HRuRh3(CO)12 in high yield. Its structural analysis was complicated by a 80–20% packing disorder. More detailed structural data were obtained from the fully ordered structure of HRuRh3(CO)10(PPh3)2, which is closely related to HRuCo3(CO)10(PPh3)2 and HFeCo3(CO)10(PPh3)2. The phosphines are axially coordinated.  相似文献   

4.
The structure of [Na(THF)2]2[Al(CH3)2C14H10]2 has been determined by three-dimensional X-ray crystallographic techniques. The compound crystallizes in the monoclinic space group B21/c, and the unit cell dimensions are a=22.610(18), b=11.256(10), c=17.589(15) Å, and β=93.27(5)°. The calculated density for eight [Na(THF)2][Al(CH3)2C14H10] monomeric units is 1.196 g/cm3. The structure has been refined by least-squares to a conventional weighted R value of 0.08. The compound exists as a centrosymmetric, contact ion-pair complex with two Na(THF)2+ cations complexed to the dimeric dianion. Two 1,4-dihydro-1,4-anthrylene groups are fused into the dianion via the two dimethylaluminum species. The average Al-C(anthrylene) bond distance of 2.060(8) Å is significantly longer than the average Al-C(methyl) bond distance of 2.002(9) Å. A discussion of the relative importance of steric and electronic effects is given. The importance of steric effects in ion-pairing is also considered.  相似文献   

5.
Ag4(Mo2O5)(SeO4)2(SeO3) has been synthesized by reacting AgNO3, MoO3, and selenic acid under mild hydrothermal conditions. The structure of this compound consists of cis-MoO22+ molybdenyl units that are bridged to neighboring molybdenyl moieties by selenate anions and by a bridging oxo anion. These dimeric units are joined by selenite anions to yield zigzag one-dimensional chains that extended down the c-axis. Individual chains are polar with the C2 distortion of the Mo(VI) octahedra aligning on one side of each chain. However, the overall structure is centrosymmetric because neighboring chains have opposite alignment of the C2 distortion. Upon heating Ag4(Mo2O5)(SeO4)2(SeO3) looses SeO2 in two distinct steps to yield Ag2MoO4. Crystallographic data: (193 K; MoKα, λ=0.71073 Å): orthorhombic, space group Pbcm, a=5.6557(3), b=15.8904(7), c=15.7938(7) Å, V=1419.41(12), Z=4, R(F)=2.72% for 121 parameters with 1829 reflections with I>2σ(I). Ag2(MoO3)3SeO3 was synthesized by reacting AgNO3 with MoO3, SeO2, and HF under hydrothermal conditions. The structure of Ag2(MoO3)3SeO3 consists of three crystallographically unique Mo(VI) centers that are in 2+2+2 coordination environments with two long, two intermediate, and two short bonds. These MoO6 units are connected to form a molybdenyl ribbon that extends along the c-axis. These ribbons are further connected together through tridentate selenite anions to form two-dimensional layers in the [bc] plane. Crystallographic data: (193 K; MoKα, λ=0.71073 Å): monoclinic, space group P21/n, a=7.7034(5), b=11.1485(8), c=12.7500(9) Å, β=105.018(1) V=1002.7(2), Z=4, R(F)=3.45% for 164 parameters with 2454 reflections with I>2σ(I). Ag2(MoO3)3SeO3 decomposes to Ag2Mo3O10 on heating above 550 °C.  相似文献   

6.
New uranyl vanadates A3(UO2)7(VO4)5O (M=Li (1), Na (2), Ag (3)) have been synthesized by solid-state reaction and their structures determined from single-crystal X-ray diffraction data for 1 and 3. The tetragonal structure results of an alternation of two types of sheets denoted S for 2[UO2(VO4)2]4− and D for 2[(UO2)2(VO4)3]5− built from UO6 square bipyramids and connected through VO4 tetrahedra to 1[U(3)O5-U(4)O5]8− infinite chains of edge-shared U(3)O7 and U(4)O7 pentagonal bipyramids alternatively parallel to a- and b-axis to construct a three-dimensional uranyl vanadate arrangement. It is noticeable that similar [UO5]4− chains are connected only by S-type sheets in A2(UO2)3(VO4)2O and by D-type sheets in A(UO2)4(VO4)3, thus A3(UO2)7(VO4)5O appears as an intergrowth structure between the two previously reported series. The mobility of the monovalent ion in the mutually perpendicular channels created in the three-dimensional arrangement is correlated to the occupation rate of the sites and by the geometry of the different sites occupied by either Na, Ag or Li. Crystallographic data: 293 K, Bruker X8-APEX2 X-ray diffractometer equipped with a 4 K CCD detector, MoKα, λ=0.71073 Å, tetragonal symmetry, space group Pm2, Z=1, full-matrix least-squares refinement on the basis of F2; 1,a=7.2794(9) Å, c=14.514(4) Å, R1=0.021 and wR2=0.048 for 62 parameters with 782 independent reflections with I?2σ(I); 3, a=7.2373(3) Å, c=14.7973(15) Å, R1=0.041 and wR2=0.085 for 60 parameters with 1066 independent reflections with I?2σ(I).  相似文献   

7.
A new layered aluminophosphate, denoted AlPO-CJ12, has been synthesized in the system Al(OPri)3-H3PO4-tetramethylethylenediamine-triethyleneglycol and its structure solved by single-crystal X-ray diffraction analysis. It is further characterized by X-ray powder diffraction, ICP, TG, DTA, and elemental analyses. The compound has an empirical formula of [Al3P4O16][(CH3)2NHCH2CH2NH(CH3)2][H3O], and crystallizes in the triclinic space group P-1 (No. 2) with a=8.9907(6) Å b=9.8359(6) Å, c=14.5566(8) Å, α=75.872(3)°, β=88.616(3)°, γ=63.404(3)°, Z=2, R1=0.0451, and wR2=0.1094. The alternation of tetrahedral AlO4 and PO3 (=O) units forms a sheet structure with a 4×6×8 network. The inorganic layers stacked in an AAAA sequence are held together by the protonated organic amine and water molecules. The co-templating role of the water molecules is studied by the calculation of the nonbonding host-guest interaction energies through a computational simulation.  相似文献   

8.
In addition to well-known dinuclear phenylselenolato palladium complexes, the reaction of [PdCl2(PPh3)2] and NaSePh affords small amounts of novel trinuclear and hexanuclear complexes [Pd3Se(SePh)3(PPh3)3]Cl (1) and [Pd6Cl2Se4(SePh)2(PPh3)6] (2). Complex 1 is triclinic, P1?, a=13.6310(2), b=16.2596(2), c=16.9899(3) Å, α=83.1738(5), β=78.9882(5), γ=78.7635(5)°. Complex 2 is monoclinic, C2/c, a=25.7165(9), b=17.6426(8), c=27.9151(14) Å, β=110.513(2)°. There are no structural forerunners for 1, but the hexanuclear complex 2 is isostructural with [Pd6Cl2Te4(TeR)2(PPh3)6] (R=Ph, C4H3S) that have been observed as one of the products in the oxidative addition of R2Te2 to [Pd(PPh3)4]. Mononuclear palladium complexes may play a significant role as building blocks in the formation of the polynuclear complexes.  相似文献   

9.
Crystals of two new layered BaNaSc(BO3)2 (I) and BaNaY(BO3)2 (II) orthoborates are grown from the melt-solution by the spontaneous crystallization onto the platinum loop. Single crystal X-ray analysis showed that the compounds are isostructural with the space group R3¯, a=5.23944(12) and 5.3338(2) Å, and c=34.5919(11) and 35.8303(19) Å for I and II, respectively, Z=6. The distinctive feature of the structure is the close-packed composite anion-cation (Ba,Na)(BO3) layers. The layers are combined into the base building packages of two types: {M3+[Ba2+(BO3)3−]2}+ and {M3+[Na+(BO3)3−]2}, where M is Sc or Y. Neutral-charge two-package (four-layer) blocks are stacked by the rhombohedral principle into twelve layers of the cubic packing.  相似文献   

10.
Syntheses and single-crystal X-ray diffraction studies have been completed on two cycloruthenapentadienyl (CO)6Ru2L2 derivatives, with L = CH2OHC = CCH2OH and C2H5C=CCH2CH2OH respectively. Crystal data are as follows: for [(CO)3RuC4(CH2OH)4]Ru(CO)3·H2O, P21/c, a 13.72(1), b 9.501(4), c 14.86(1) Å, β 101.10(6)°, Rw = 0.052 for 1911 reflections; for [(CO)3RuC4(CH2CH2OH)2(C2H5)2]Ru(CO)3, P21/c, a 9.191(3), b 16.732(4), c 14.903(3) Å, β 113.61(4)°, Rw = 0.042 for 2865 reflections. Both compounds are built up from binuclear units, each unit being regarded as a Ru(CO)3 fragment π-bonded to a cycloruthenapentadienyl ring. The molecular parameters are compared with those of known cyclometallapentadienyl complexes of transition metals. The presence of a semi-bridging CO group is discussed.  相似文献   

11.
The two new compounds, Sr4Cu3(AsO4)2(AsO3OH)4·3H2O (1) and Ba2Cu4(AsO4)2(AsO3OH)3(2), were synthesized under hydrothermal conditions. They represent previously unknown structure types and are the first compounds synthesized in the systems SrO/BaO-CuO-As2O5-H2O. Their crystal structures were determined by single-crystal X-ray diffraction [space group C2/c, a=18.536(4) Å, b=5.179(1) Å, c=24.898(5) Å, β=93.67(3)°, V=2344.0(8) Å3, Z=4 for 1; space group P42/n, a=7.775(1) Å, c=13.698(3) Å, V=828.1(2) Å3, Z=2 for 2]. The crystal structure of 1 is related to a group of compounds formed by Cu2+-(XO4)3− layers (X=P5+, As5+) linked by M cations (M=alkali, alkaline earth, Pb2+, or Ag+) and partly by hydrogen bonds. In 1, worth mentioning is the very short hydrogen bond length, D···A=2.477(3) Å. It is one of the examples of extremely short hydrogen bonds, where the donor and acceptor are crystallographically different. Compound 2 represents a layered structure consisting of Cu2O8 centrosymmetric dimers crosslinked by As1φ4 tetrahedra, where φ is O or OH, which are interconnected by Ba, As2 and hydrogen bonds to form a three-dimensional network. The layers are formed by Cu2O8 centrosymmetric dimers of CuO5 edge-sharing polyhedra, crosslinked by As1O4 tetrahedra. Vibrational spectra (FTIR and Raman) of both compounds are described. The spectroscopic manifestation of the very short hydrogen bond in 1, and ABC-like spectra in 2 were discussed.  相似文献   

12.
α-Ca3(BN2)2 crystallizes in the cubic system (space group: ) with one type of calcium ions disordered over of equivalent (8c) positions. An ordered low-temperature phase (β-Ca3(BN2)2) was prepared and found to crystallize in the orthorhombic system (space group: Cmca) with lattice parameters: , , and . Structure refinements on the basis of X-ray powder data have revealed that orthorhombic β-Ca3(BN2)2 corresponds to an ordered super-structure of cubic α-Ca3(BN2)2. The space group Cmca assigned for β-Ca3(BN2)2 is derived from by a group-subgroup relationship.DSC measurements and temperature-dependent in situ X-ray powder diffraction studies showed reversible phase transitions between β- and α-Ca3(BN2)2 with transition temperatures between 215 and 240 °C.The structure Sr3(BN2)2 was reported isotypic with α-Ca3(BN2)2 () with one type of strontium ions being disordered over of equivalent (2c) positions. In addition, a primitive () structure has been reported for Sr3(BN2)2. Phase stability studies on Sr3(BN2)2 revealed a phase transition between a primitive and a body-centred lattice around 820 °C. The experiments showed that both previously published structures are correct and can be assigned as α-Sr3(BN2)2 (, high-temperature phase), and β-Sr3(BN2)2 (, low-temperature phase).A comparison of Ca3(BN2)2 and Sr3(BN2)2 phases reveals that the different types of cation disordering present in both of the cubic α-phases () have a directing influence on the formation of two distinct (orthorhombic and cubic) low-temperature phases.  相似文献   

13.
Anodic voltammetry and electrolysis of the metallocenes ferrocene, ruthenocene, and nickelocene have been studied in dichloromethane containing two different fluorine-containing anions in the supporting electrolyte. The perfluoroalkoxyaluminate anion [Al(OC(CF3)3)4] has very low nucleophilicity, as shown by its inertness towards the strong electrophile [RuCp2]+ and by computation of its electrostatic potential in comparison to other frequently used electrolyte anions. The low ion-pairing ability of this anion was shown by the large spread in E1/2 potentials (ΔE1/2 = 769 mV) for the two one-electron oxidations of bis(fulvalene)dinickel. The hexafluoroarsenate anion [AsF6], on the other hand, reacts rapidly with the ruthenocenium ion and is much more strongly ion-pairing towards oxidized bis(fulvalene)dinickel (ΔE1/2 = 492 mV). In terms of applications of these two anions to the anodic oxidation of organometallic sandwich complexes, the behavior of [Al(OC(CF3)3)4] is similar to that of other weakly-coordinating anions such as [B(C6F5)4], whereas that of [AsF6] is similar to the more traditional electrolyte anions such as [PF6] and [BF4]. Additionally, the synthesis and crystal structure of [Cp2Fe][Al(OC(CF3)3)4] are reported.  相似文献   

14.
Cerium(III) diammonium polyphosphate, (NH4)2Ce(PO3)5, is triclinic P1 with the following unit cell dimensions: a = 7.241(5) Å, b = 13.314(8) Å, c = 7.241(5)Å, α = 90.35(5)°, β′ = 107.50(5)°, γ = 90.28(5)°, and Z = 2, V = 665.7 Å3, Dx = 2.85 g/cm3. The crystal structure of this new type of polyphosphate has been solved and refined from 4130 independent reflections to a final R value 0.029. The most interesting feature of this salt is the existence of two infinite crystallographically nonequivalent (PO3)? chains, one running parallel to the a axis, the other along the c axis, both with a period of five tetrahedra. This compound seems to be the first example of a long chain polyphosphate with crystallographic independent chains.  相似文献   

15.
The new complex Ru3(CO)9(PPh2H)3 (I) was prepared by the direct thermal reaction of Ru3(CO)12 with PPh2 H and was spectroscopically characterized. Irradiation of I with λ ≥ 300 nm leads to the formation of Ru2(μ-PPh2)2(CO)6 (II) and three new phosphido-bridged complexes, Ru3(μ-H)2(μ-PPh2)2(CO)8 (III), Ru3(μ-H)2(μ-PPh2)2(CO)7(PPh2H) (IV) and Ru3(μ-H)(μ-PPh2)3(CO)7 (V). These complexes have been characterized spectroscopically and Ru3 (μ-H)(μ-PPh2)3(CO)7 by a complete single crystal X-ray structure determination. It crystallizes in the space group P21/n with a 20.256(3), b 22.418(6), c 20.433(5) Å, β 112.64(2)°, V 8564(4) Å3, and Z = 8. Diffraction data were collected on a Syntex P21 automated diffractometer using graphite-monochromatized Mo-Kα radiation, and the structure was refined to RF 4.76% and RwF 5.25% for the 8,847 independent reflections with F0 > 6σ(F0). The structure consists of a triangular array of Ru atoms with seven terminal carbonyl ligands, three bridging diphenylphosphido ligands which bridge each of the RuRu bonds, and the hydride ligand which bridges one RuRu bond. Complex IV was also shown to give V upon photolysis and is thus an intermediate in the photoinduced formation of V from I.  相似文献   

16.
The structural and energetic characteristics of the lowest-lying structures for isolated molecules and ions of light-metal boro- and aluminohydrides L(MH4)4, HL(MH4)3, H2L(MH4)2, and H3L(MH4) (L = Al, Sc, Ti, V, Cr; M = B, Al) with different coordination modes of BH4- and AlH4 groups were calculated by the perturbation theory (MP2), coupled cluster (CCSD(T)), and density functional theory (B3LYP) methods using the 6-31G*, 6-311+G**, and 6-311++G** basis sets. The results are compared with the computational data obtained at the same level of theory for related complexes L(MH4)3, HL(MH4)2, H2L(MH4), L(MH4)2, and HL(MH4). The preferable coordination modes of the ligands in these complexes are analyzed, and the energies of dissociation with elimination of BH3 (AlH3) molecules and BH4 (AlH4) anions in various series of related hydroborates and hydroaluminates are estimated. The structure and relative stability of classical hydride and (μ-H2)-hydrogen complexes in the H2L (MH4)2 and H3L(MH4) systems are discussed. Original Russian Text ? O.P. Charkin, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 6, pp. 1015–1024.  相似文献   

17.
The molecular and crystal structure of tris(bistrimethylsilylamin)thallium was determined by means of single-crystal X-ray spectroscopy: in the space group P31c with a = 16.447(7), c = 8.456(7) Å; and Dc = 1.149 g cm?3 two molecules are located in the unit cell. The compound is isomorphous to the analogues Fe[N(SiMe3)2]3 or Al[N(SiMe3)2]3, respectively, which show a propellar-twist of the Si2N-groups versus the plane of the metal atom and the three nitrogen-atoms: Tl(N)3/Si2N 49.1°; SiNSi 122.6°; NSiC 111.8°; CSiC 107.1°; TlN 2.089 Å;; SiN 1.738 Å;; SiC 1.889 Å;.  相似文献   

18.
Pentavalent bis(triorganosiloxy)triphenylantimony derivatives, Ph3Sb(OSiR3)2 (R = Me, Ph), were synthesized by reaction of triphenylantimony with trimethyl- or triphenylsilanol in the presence of tert-butylhydroperoxide by the mild reaction conditions (0-5 °C, 2 h). The reaction of triphenylantimony with diethanolamine in the presence of tert-butylhydroperoxide gave the cyclic compound Ph3Sb(OCH2CH2)2NH. The mixture of Ph3SbO and Ph3Sb(OCH2CH2NMe2)2 was obtained by the reaction of triphenylantimony with 2-(N,N-dimethylamino)ethanol in the presence of tert-butylhydroperoxide.  相似文献   

19.
The uranyl and neptunyl(VI) iodates, K3[(UO2)2(IO3)6](IO3)·H2O (1) and K[NpO2(IO3)3]·1.5H2O (2), have been prepared and crystallized under mild hydrothermal conditions. The structures of 1 and 2 both contain one-dimensional 1[AnO2(IO3)3]1−(An=U,Np) ribbons that consist of approximately linear actinyl(VI) cations bound by iodate anions to yield AnO7 pentagonal bipyramids. The AnO7 units are linked by bridging iodate anions to yield chains that are in turn coupled by additional iodate anions to yield ribbons. The edges of the ribbons are terminated by monodentate iodate anions. For 1 and 2, K+ cations and water molecules separate the ribbons from one another. In addition, isolated iodate anions are also found between 1[UO2(IO3)3]1− ribbons in 1. In order to aid in the assignment of oxidation states in neptunyl containing compounds, a bond-valence sum parameter of 2.018 Å for Np(VI) bound exclusively to oxygen has been developed with b=0.37 Å. Crystallographic data (193 K, MoKα, λ=0.71073): 1, triclinic, , a=7.0609(4) Å, b=14.5686(8)  Å, c=14.7047(8)  Å, α=119.547(1)°, β=95.256(1)°, γ=93.206(1)°, Z=2, R(F)=2.49% for 353 parameters with 6414 reflections with I>2σ(I); (203 K, MoKα, λ=0.71073): 2, monoclinic, P21/c, a=7.796(4)  Å, b=7.151(3)  Å, c=21.79(1)  Å, β=97.399(7)°, Z=4, R(F)=6.33% for 183 parameters with 2451 reflections with I>2σ(I).  相似文献   

20.
Two new potassium uranyl molybdates K2(UO2)2(MoO4)O2 and K8(UO2)8(MoO5)3O6 have been obtained by solid state chemistry . The crystal structures were determined by single crystal X-ray diffraction data, collected with MoKα radiation and a charge coupled device (CCD) detector. Their structures were solved using direct methods and Fourier difference techniques and refined by a least square method on the basis of F2 for all unique reflections, with R1=0.046 for 136 parameters and 1412 reflections with I?2σ(I) for K2(UO2)2(MoO4)O2 and R1=0.055 for 257 parameters and 2585 reflections with I?2σ(I) for K8(UO2)8(MoO5)3O6. The first compound crystallizes in the monoclinic symmetry, space group P21/c with a=8.250(1) Å, b=15.337(2) Å, c=8.351(1) Å, β=104.75(1)°, ρmes=5.22(2) g/cm3, ρcal=5.27(2) g/cm3 and Z=4. The second material adopts a tetragonal unit cell with a=b=23.488(3) Å, c=6.7857(11) Å, ρmes=5.44(3) g/cm3, ρcal=5.49(2) g/cm3, Z=4 and space group P4/n.In both structures, the uranium atoms adopt a UO7 pentagonal bipyramid environment, molybdenum atoms are in a MoO4 tetrahedral environment for K2(UO2)2(MoO4)O2 and MoO5 square pyramid coordination in K8(UO2)8(MoO5)3O6. These compounds are characterized by layered structures. The association of uranyl ions (UO7) and molybdate oxoanions MoO4 or MoO5, give infinite layers [(UO2)2(MoO4)O2]2− and [(UO2)8(MoO5)3O6]8− in K2(UO2)2(MoO4)O2 and K8(UO2)8(MoO5)3O6, respectively. Conductivity properties of alkali metal within the interlayer spaces have been measured and show an Arrhenius type evolution.  相似文献   

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