非等温TG- DTG法确定2,2''- 联吡啶- 对甲氧基苯甲酸铕(Ⅲ)热分解反应的机理函数和动力学参数

采用TG-DTG和DTA技术研究了2,2'-联吡啶-对甲氧基苯甲酸铕(Ⅲ)在静态空气中的非等温热分解过程及动力学,根据TG曲线确定了热分解过程中的中间产物及最终产物,运用微分法与积分法对非等温动力学数据进行分析,推断出第一步的动力学方程为dα/dt=Aexp(-E/RT)2(1-α)1/2.     

邻甲基苯甲酸铕与邻啡咯啉络合物的热分解动力学及寿命

采用TG DTG技术研究了Eu2 (o MBA) 6 (PHEN) 2 (o MBA :邻甲基苯甲酸根离子 ;PHEN :1 ,1 0 邻啡咯啉 )在静态空气中的非等温热分解机理及动力学。根据TG曲线确定了热分解过程中的中间产物及最终产物。运用Acher法、Madhusudanan Krishnan Ninan (MKN)法和Ozawa法对非等温动力学数据进行分析 ,得到第一步热分解反应的机理函数和动力学参数 ,同时用等温TG法得到失重 1 0 %为寿终指标的寿命方程 :lnτ=-2 4 3 690 +1 .5 2 84× 1 0 4 T。     

双核铕-苯甲酸-邻菲咯啉三元络合物非等温热分解动力学研究

采用TG-DTG和DTA技术研究了Eu2(BA)6(PHEN)2 (BA苯甲酸根离子;PHEN1,10-邻菲咯啉)在静态空气中的热分解过程,根据TG曲线确定了热分解过程中的中间产物及最终产物,运用Acher法、Madhusudanan-Krishnan-Ninan (MKN)法和Flynn-Wall-Ozawa法对非等温动力学数据进行分析,推断出第一步热分解反应的动力学方程为dα/dt=Aexp(-E/RT)(1-α)2, 第一步热分解反应的活化能为135 kJ/mol, 活化自由能ΔG为149 kJ/mol, 活化焓ΔH为129 kJ/mol, 活化熵ΔS为-33 J/(mol·k), 同时用等温TG法得到失重10%为寿终指标的寿命方程为lnτ=-22.66+1.646×104/T.     

反式二氯四吡啶合钴(Ⅱ)水合物的结构和非等温热分解动力学

利用X射线四圆衍射仪测定了标题化合物的晶体结构.晶体属空间群P2~1/n,a=0.9361(6)nm,b=1.6728(9)nm,c=1.3878(7)nm,β=94.01(5)°,Z=4,以TG和DTG技术研究了化合物的热分解过程. 分别运用积分法和微分法对该化合物第一步热分解的非等温动力学数据进行分析,推断为球对称的三维扩散机理,其非等温动力学方程式为dα/dt=A·e^-^E^/^R^T·3/2(1-α)^2^/^3·[1-(1-α)^1^/^3]^-^1, 动力学补偿效应表达式为lnA=0.3341E-2.715     

三水和硝酸N,N,N"'-四[(1'-苄基-2'-苯并咪唑)甲基]-1,2- 环已二胺合Zn(Ⅱ)的晶体结构和非等温热分解反应动力学

本文报道标题Zn(Ⅱ)配合物:[Zn(NBOCTB)](NO~3)~2.3H~2O的制备,晶体结构及热分解动力学,该晶体属三斜晶系,空间群PI,a=1.4146(2),B=1.5407(3),c=1.8518(4)nm;α=62.09(2).β=72.46(2),68.60(1)°. 并对配合物第一和第二步热分解反应进行了非等温动力学研究.运用Achar法与Coats-Redfern 法对非等温动力学数据进行分析,推断第一步脱水过程为成核生长机理,其动力学方程为d α/dt=Ae^-^E^/^R^T.3/2(1-α).[-ln(1-α) ] ^1^/^3; 动力学补偿效应表达式lnA= 0.3739E- 3. 321. 第二步分解过程为二级化学反应, 其动力学方程为:dα/dt=Ae^E^/^r^t(1-α)^2;动力学补偿效应表达式为lnA=0.2100E-3.690.     

三水和硝酸N,N,N"'-四[(1'-苄基-2'-苯并咪唑)甲基]-1,2- 环已二胺合Zn(Ⅱ)的晶体结构和非等温热分解反应动力学

本文报道标题Zn(Ⅱ)配合物:[Zn(NBOCTB)](NO~3)~2.3H~2O的制备,晶体结构及热分解动力学,该晶体属三斜晶系,空间群PI,a=1.4146(2),B=1.5407(3),c=1.8518(4)nm;α=62.09(2).β=72.46(2),68.60(1)°. 并对配合物第一和第二步热分解反应进行了非等温动力学研究.运用Achar法与Coats-Redfern 法对非等温动力学数据进行分析,推断第一步脱水过程为成核生长机理,其动力学方程为d α/dt=Ae^-^E^/^R^T.3/2(1-α).[-ln(1-α) ] ^1^/^3; 动力学补偿效应表达式lnA= 0.3739E- 3. 321. 第二步分解过程为二级化学反应, 其动力学方程为:dα/dt=Ae^E^/^r^t(1-α)^2;动力学补偿效应表达式为lnA=0.2100E-3.690.     

三水合硝酸N,N,N′,N′-四[(1′-苄基-2′-苯并咪唑)甲基]-1,2-环己二胺合Zn(Ⅱ)的晶体结构和非等温热分解反应动力学

本文报道标题Zn(Ⅱ)配合物:[Zn(NBOCTB)](NO_3)_2·3H_2O的制备,晶体结构及热分解动力学.该晶体属三斜晶系,空间群p(?),a=1.4146(2),b=1.5407(3),c=1.8518(4)nm;α=62.09(2),β=72.46(2),γ=68.60(1)°.并对配合物第一和第二步热分解反应进行了非等温动力学研究.运用Achar法与Coats—Redfern法对非等温动力学数据进行分析,推断第一步脱水过程为成核和生长机理,其动力学方程为:dα/dt=Ae~(-E/RT),3/2(1-α)·[-In(1-α)]~(1/3);动力学补偿效应表达式为:InA=0.3739E-3.321.第二步分解过程为二级化学反应,其动力学方程为:dα/dt=Ae~(-E/RT)(1-α)~2;动力学补偿效应表达式为:InA=0.2100E-3.690.     

9,10-二氰基蒽敏化光氧化反应的溶剂效应

本文通过α,β-蒎烯及1,4-二苯基-1,3-丁二烯的9,10-二氰基蒽(DCA)敏化光氧化反应在一系列溶剂中产物生成的相对量子效率及单线态氧(¹O₂)产物的含量,对β-蒎烯在乙腈中的反应动力学分析,讨论了反应的溶剂效应,证明了DCA敏化光氧化反应,包括¹O₂产物都是经由电子转移的反应机理。     

乙醇—丙烯酸体系中乙醇的γ辐解研究

研究了乙醇-丙烯酸体系在低剂量下的γ辐解产物H_2、2,3-丁二醇及乙醛的生成.结果表明,乙醛不是在α-羟乙基自由基的歧化反应中生成的,而是来源于刺迹中的快反应;在该体系中丙烯酸(未与溶剂化电子反应)可清除H原子,其反应速率常数k_4=7.5×10~(9)mol~(-1)s~(-1);2,3-丁二醇由α-羟乙基自由基的再结合反应生成,动力学方程可表示为:G=G_0—[k_(11)/2(k_10)~(1/2)](G/K'D)~(1/2)[AAH].     

电荷转移盐(C_3H_5N_2H)_3[PMo_(12)O_(40)]的合成与热分解及光致变色反应动力学

用磷钼酸与咪唑合成了一种新的杂多酸-有机电荷转移盐(C3H5N2H)3[PMo12O40]。通过元素分析、红外光谱、固体漫反射光谱、电子自旋共振及热分析等测试技术对其进行了表征,用单扫描法(Achar法和Coats-Redfern法)对合成化合物的TG分析结果进行了非等温热分解动力学研究。推断结果表明,合成化合物的第1步热分解为球对称的三维扩散机理(n=2),其动力学方程为dα/dt=1.58×108[1-(1-α)1/3]-1(1-α)2/3exp(-40931.0/T),求得分解反应的表观活化能E=340.30kJ/mol,指前因子A=1.05×108s-1。标题化合物对紫外光具有光致变色性质,用固体漫反射光谱研究了其光致变色反应动力学。结果显示,其光致变色反应表现为一级或准一级动力学,速率常数k=9.80×10-5s-1。     

Silylene hydride complexes of molybdenum with silicon-hydrogen interactions: neutron structure of (eta(5)-C(5)Me(5))(Me(2)PCH(2)CH(2)PMe(2))Mo(H)(SiEt(2))

Reduction of CpMoCl(4) with 3.1 equiv of Na/Hg amalgam (1.0% w/w) in the presence of 1 equiv of dmpe and 1 equiv of trimethylphosphine afforded the molybdenum(II) chloride complex Cp(dmpe)(PMe(3))MoCl (1) (Cp = 1,2,3,4,5-pentamethylcyclopentadienyl, dmpe = 1,2-bis(dimethylphosphino)ethane). Alkylation of 1 with PhCH(2)MgCl proceeded in high yield to liberate PMe(3) and give the 18-electron pi-benzyl complex Cp(dmpe)Mo(eta(3)-CH(2)Ph) (2). Variable temperature NMR experiments provided evidence that 2 is in equilibrium with its 16-electron eta(1)-benzyl isomer [Cp(dmpe)Mo(eta(1)-CH(2)Ph)]. This was further supported by reaction of 2 with CO to yield the carbonyl benzyl complex Cp(dmpe)(CO)Mo(eta(1)-CH(2)Ph) (3). Complex 2 was found to react with disubstituted silanes H(2)SiRR' (RR' = Me(2), Et(2), MePh, and Ph(2)) to form toluene and the silylene complexes Cp(dmpe)Mo(H)(SiRR') (4a: RR' = Me(2); 4b: RR' = Et(2); 4c: RR' = MePh; 4d: RR' = Ph(2)). Reactions of 2 with monosubstituted silanes H(3)SiR (R = Ph, Mes, Mes = 2,4,6-trimethylphenyl) produced rare examples of hydrosilylene complexes Cp(dmpe)Mo(H)Si(H)R (5a: R = Ph; 5b: R = Mes; 5c: R = CH(2)Ph). Reactivity of complexes 4a-c and 5a-d is dominated by 1,2-hydride migration from metal to silicon, and these complexes possess H.Si bonding interactions, as supported by spectroscopic and structural data. For example, the J(HSi) coupling constants in these species range in value from 30 to 48 Hz and are larger than would be expected in the absence of H.Si bonding. A neutron diffraction study on a single crystal of diethylsilylene complex 4b unequivocally determined the hydride ligand to be in a bridging position across the molybdenum-silicon bond (Mo-H 1.85(1) A, Si-H 1.68(1) A). The synthesis and reactivity properties of these complexes are described in detail.     

Syntheses and structures of the infinite chain compounds Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14)

The alkali metal/group 4 metal/polychalcogenides Cs(4)Ti(3)Se(13), Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) have been synthesized by means of the reactive flux method at 823 or 873 K. Cs(4)Ti(3)Se(13) crystallizes in a new structure type in space group C(2)(2)-P2(1) with eight formula units in a monoclinic cell at T = 153 K of dimensions a = 10.2524(6) A, b = 32.468(2) A, c = 14.6747(8) A, beta = 100.008(1) degrees. Cs(4)Ti(3)Se(13) is composed of four independent one-dimensional [Ti(3)Se(13)(4-)] chains separated by Cs(+) cations. These chains adopt hexagonal closest packing along the [100] direction. The [Ti(3)Se(13)(4-)] chains are built from the face- and edge-sharing of pentagonal pyramids and pentagonal bipyramids. Formal oxidation states cannot be assigned in Cs(4)Ti(3)Se(13). The compounds Rb(4)Ti(3)S(14), Cs(4)Ti(3)S(14), Rb(4)Hf(3)S(14), Rb(4)Zr(3)Se(14), Cs(4)Zr(3)Se(14), and Cs(4)Hf(3)Se(14) crystallize in the K(4)Ti(3)S(14) structure type with four formula units in space group C(2)(h)()(6)-C2/c of the monoclinic system at T = 153 K in cells of dimensions a = 21.085(1) A, b = 8.1169(5) A, c = 13.1992(8) A, beta = 112.835(1) degrees for Rb(4)Ti(3)S(14);a = 21.329(3) A, b = 8.415(1) A, c = 13.678(2) A, beta = 113.801(2) degrees for Cs(4)Ti(3)S(14); a = 21.643(2) A, b = 8.1848(8) A, c = 13.331(1) A, beta = 111.762(2) degrees for Rb(4)Hf(3)S(14); a = 22.605(7) A, b = 8.552(3) A, c = 13.880(4) A, beta = 110.919(9) degrees for Rb(4)Zr(3)Se(14); a = 22.826(5) A, b = 8.841(2) A, c = 14.278(3) A, beta = 111.456(4) degrees for Cs(4)Zr(3)Se(14); and a = 22.758(5) A, b = 8.844(2) A, c = 14.276(3) A, beta = 111.88(3) degrees for Cs(4)Hf(3)Se(14). These A(4)M(3)Q(14) compounds (A = alkali metal; M = group 4 metal; Q = chalcogen) contain hexagonally closest-packed [M(3)Q(14)(4-)] chains that run in the [101] direction and are separated by A(+) cations. Each [M(3)Q(14)(4-)] chain is built from a [M(3)Q(14)] unit that consists of two MQ(7) pentagonal bipyramids or one distorted MQ(8) bicapped octahedron bonded together by edge- or face-sharing. Each [M(3)Q(14)] unit contains six Q(2)(2-) dimers, with Q-Q distances in the normal single-bond range 2.0616(9)-2.095(2) A for S-S and 2.367(1)-2.391(2) A for Se-Se. The A(4)M(3)Q(14) compounds can be formulated as (A(+))(4)(M(4+))(3)(Q(2)(2-))(6)(Q(2-))(2).     

Trimethylphosphine complexes of tungsten(O) and (IV). X-ray crystal structures of trimethylphosphine tris (phenylacetylene) tungsten(O); bis(trimethylphosphine) tetrakis (methylisocyanide) tungsten(O), and oxodichlorotris (trimethylphosphine) tungsten (IV)

The reduction of WCl₄(PMe₃)₃ by sodium amalgam in presence of phenylacetylene gives W(PMe₃)(PhCCH)₃ (A). Reduction in presence of methylisocyanide gives W(PMe₃)₂(MeNC)₄ (B), while in presence of excess PMe₃ in tetrahydrofuran under hydrogen, WH₂Cl₂(PMe₃)₄ (C) is formed. The reaction of WCl₂(PMe₃)₄ with methanol in tetrahydrofuran gives mixtures of WH₂Cl₂(PMe₃)₄ and WOC1₂(PMe₃)₃ (D).The structures of A, B, and D have been determined by X-ray diffraction.     

Crystal structure of (acetylacetonato) (dicarbonyl)iridium(I)

The structure of Ir(CO)₂(acac) is determined by XRD at room temperature. Crystallographic data for C₇H₇IrO₄ are: a = 6.4798(5) ?, b = 7.7288(5) ?, c = 9.1629(10) ?, α = 105.738(2)°, β = 90.467(3)°, γ = 100.658(2)°, space group 1, P , V= 433.24(6) ?³, Z = 2, d _calc = 2.662 g/cm³, R = 0.0167. The structure is built of isolated mononuclear molecules. The central iridium atom has a square coordination environment formed by two oxygen atoms that belong to the acetylacetonate ligand and two carbon atoms of carbonyl groups. The average Ir-O and Ir-C bond lengths are 2.045(3) ? and 1.832(6) ? respectively. Molecules are stacked in such a way that the planes of coordination squares turn out to be parallel to the Ir...Ir distances between the nearest neighbors in the stack of 3.242 ? and 3.260 ?. Original Russian Text Copyright ? 2009 by K. V. Zherikova, N. V. Kuratieva, and N. B. Morozova __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 595–597, May–June, 2009.