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1.
By using a micro-bomb calorimeter, the standard enthalpies of combustion of C60 and C70 have been determined to be - (25 947.1±8.5) and - (29 956.1 ± 8.9) kJ/mol respectively. A g. 1. c. analysis indicated that the amounts of residual organic solvents in the samples were very small, and their effects on the final results were negligible. The energy of combustion ofC60 determined in this work is in agreement in the uncertainty interval with that determined by means of traditional calorimeter using macro amount of sample. The enthalpies of formation of these two substances have been derived. The strain energies in the molecules of C60 and C70 were estimated by a bond energy scheme and by using corannulene as the model compound, the results estimated from different methods are very close. Project supported by the National Natural Science Foundation of China (Grant No. 29473143)  相似文献   

2.
安绪武  陈斌  何俊 《物理化学学报》1997,13(11):961-964
富勒烯是新发现的一类碳的稳定单质,其分子骨架中含有多个五员环及非平面球壳状大力键.与全为六员环的平面大r键的石墨结构相比,这些张力提高了分子能量.通过富勒烯的生成焰的测定,对了解这些分子的稳定性和反应性,它们的生成机理,以及研究分子的结构与能量的规律是很有意  相似文献   

3.
活性碳用苯胺处理后,可以减少对C_(60)和C_(70)的不可逆吸附,从而增加C_(60)和C_(70)的分离收率,同时提高了C_(70)的纯度。  相似文献   

4.
We have theoretically investigated the one- and two-photon absorption properties of C60 and C70 using the ZINDO method. From the results it is suggested that the one-photon absorption spectra are in agreement with the experimental observations. It is found that the maximum TPA cross section of C70 is more than twice that of C60,which is consistent with the experimental results. A notable point is that the TPA process of C60 is different from that of C70 as well as other ordinary conjugated molecules.  相似文献   

5.
Sincegramquantitiesoffullereneswereseparatedfromcarbonsoots,manystudieshavebeentriggeredontheirstructures,propertiesandreactions.Asfullerenescanproduceveryhighquantumyieldsofsingletoxygenwhileexcitedbylight,moreinteresthasbeenfocusedontheexaminationoft…  相似文献   

6.
C60和C70在几种溶剂中的溶解度与温度的关系   总被引:5,自引:0,他引:5  
溶解度是富勒烯C6O和C7O的基本物理化学常数之·.自电弧法合成富勒烯成功以后*;人们就很重视C60和C7O在各种溶剂中的溶解性能.由于在分离、分析富勒烯和研究其化学反应时,往往是在溶液中进行的,因此,不少科学家很快就测定TC60和C70室温下在多种有机溶剂中的溶解度[’-  相似文献   

7.
曾和平 《化学学报》2002,60(9):1543-1547
用激光光解方法研究了富勒烯(C_(60)/C_(70))与三苯基胺(TPA)间的光诱 导电子转移过程。在近红外区,观测到TPA阴离子自由基,富勒烯(C_(60)/C_(70) )激发三线态和阴离子自由基。在苯腈溶液中,利用瞬态谱测定了电子从TPA转移 到富勒烯(C_(60)/C_(70))激发三线态的量子转化产率(Φ_(et))和电子转移常 数(k_(et))。  相似文献   

8.
C_(60)、C_(70)与过氧苯甲酰反应的动力学研究胡波,薛万华,张法义,尚振锋,马克勤,臧雅茹,赵学庄(南开大学化学系,天津,300071)关键词C_(60),C_(70),动力学Kratschmer等人[1]的发现使制备宏观量的C(60)和C(70...  相似文献   

9.
1990年Kratschmer[1,2]等人实现了C60和C70的宏观量制备后,有关fullerene的化学研究迅速展开[3-5].业已发现C60具有极为丰富的化学性质.在对C60化学性质的认识过程中,气相离子化学一直起着重要的作用[6].Roth等人[7]在ICR质谱仪中,制得了C60外部键合金属的衍生物C60M+;Caldwell及合作者[8]在质谱仪上,利用高动能的C60与轻气体(He,Ne,H2,D2)碰撞,得到了笼内包含轻气体原子的C60;Bohme[9,10]等人在流动后辉光质谱仪上,系统地研究了C60的单、双、三电荷离子与多种有机物的反应,获得了相应的C60加合…  相似文献   

10.
The enthalpies of combustion (ΔH comb) of five primary, secondary, and tertiary alkyl(aryl)arsines in the condensed state were calculated using the equation ΔH comb = −385.8–110.3N, where N is the number of bond-forming electrons. The dependence presented is used for the calculation of the enthalpies of combustion of full esters and amidoesters of arsinous acid of noncyclic and cyclic structures. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1042–1043, May, 2007.  相似文献   

11.
The rotation dynamics of C60 molecules in organic superconductor K3C60 has been investigated from the viewpoint of intramolecular interaction.It is determined that the rotation of C60 at room temperature has been frozen up within a small region of rotation angle (0→50°),and pointed out that the reason for the freeze is the physical interaction rather than the geometrical hindrance.The computations of the interactions for alkali-doped compounds A3-xAxC60(x=1,2,3;A,A'= K,Rb,Cs) other than K3C60 have also been carried out.From the obtained results,it is seen that the superconducting transition temperatures Tc are strongly connected with the interactions in them,and this observation is consistent with the discovery of the correlation between Tc and lattice constants a  相似文献   

12.
孙娜  郭志新  朱道本 《有机化学》2002,22(7):462-475
以六加成反应为代表的C60的多加成反应已经成为富勒烯化学的一个重要组成 部分。综述了C60的六加成反应,包括具有不同对称性的各种C 60六加成产物的合 成和表征,以及六加成产物的基本性质和应用。  相似文献   

13.
The construction of adsorptive type C60 modified electrode and its electrochemical reduction and oxidation behavior in aqueous solutions are described in this report. Four pairs of one-electron transfer reduction and oxidation cyclic voltammetry is obtained in aqueous solution containing 30% CH3CN and 2% (C2H5)4NOH. It is reported in this paper that the C60 modified electrode also catalyzes the electrochemical reduction of dissolved oxygen in 40% DMF and 2% (C2H5)4NOH aqueous solution and this might open a new field for the potential applications of C60 in electrochemistry and electroaualytical chemistry.  相似文献   

14.
Summary The energies of combustion of crystalline L-α-glutamic and 6-aminohexanoic acids were measured in a static bomb adiabatic calorimeter, in pure oxygen at 3040 kPa. Corrections were made for the heats due to the ignition of sample and for the nitric acid formation. The derived enthalpies of formation for L-α -glutamic and 6-aminohexanoic acids are ΔfHcr0= -1002.6±1.1 kJ mol-1and ΔfHcr0= -641.6±1.2 kJ mol-1, respectively. The data of enthalpy of formation are compared with literature values and with estimated values by means of group additivity, using parameters recommended by Domalski and Hearing.  相似文献   

15.
利用分子组装技术制备了C60 有序分子膜 ,利用光电谱研究了C60 有序分子膜光电特性。结果表明 ,C60 具有特殊的光电行为 ,作为良电子受体 ,在n -Si表面上表现出了与通常染料分子截然不同的光电荷转移特性。  相似文献   

16.
活性碳分离碳—60和碳—70   总被引:1,自引:0,他引:1  
荣廷文  钱银娥 《应用化学》1994,11(3):112-114
活性碳用苯胺处理后,可以减少对C60和C70的不可逆吸附,从而增加C60和C70的分离收率,同时提高了C70的纯度。  相似文献   

17.
C60衍生物与C60混合物中富勒烯的生长研究   总被引:1,自引:0,他引:1  
富勒烯分子生长方面的研究,对于富勒烯的基础研究以及潜在应用有着重要的意义,因此引起了科学界的广泛兴趣和研究,Yeretzian[1]、Campbell[2],Rao[3]等人相继用不同的实验方法对C60的融合作了详细研究,但C60的生长动力学过程依然是个悬而未决的问题.我们实验室已对C60的正负离子解离以及C60加成衍生物中C60的解离和生长作了较深入的研究:发现C60正负离子解离时电荷具有不同的转移通道,即C朋解离时电荷留在碳笼上,而C60解离时电荷易转移到小碳簇上,且C60解离以较缓慢的笼子收缩过程进行间.衍生物基团(如节基、薛基)对C。。…  相似文献   

18.
Youngman MJ  Green DB 《Talanta》1999,48(5):1993-1206
Microwave-assisted extraction (MAE) was examined as an alternative to the traditional Soxhlet method of extracting C60 and C70 from fullerene soot. MAE of 0.20 g of fullerene soot with 95:5 toluene–acetonitrile yielded greater than 7.8 mg of C60 and greater than 0.54 mg of C70 in 4 min with no further increase in yield after 30 min of irradiation. By comparison, exhaustive Soxhlet extraction of the same size sample with the same solvent yielded 7.1 mg of C60 and 0.58 mg of C70 in 340 min. Reextraction by MAE of soot initially extracted by Soxhlet increased the yield of Soxhlet alone. Although MAE was limited to less than 0.5-g sample per extraction vessel, multiple samples were extracted with minimal increased extraction time and no reduction in the amount of material recovered.  相似文献   

19.
C60O结构和电子光谱的理论研究   总被引:1,自引:0,他引:1  
用INDO系列方法研究C60O的两种结构:一是桥氧加在2个六元环之间的键上为C2v构型;另一个是桥氧加在1个五元环和1个六元环之间的键上为Cs构型。计算表明,从总能量、HOMO-LUMO能级差和光谱性质看,C60O的稳定构型都应是C2v构型,该C2v异构体具有环氧结构(桥C15-C30键长为0.1518nm,键序为0.8744),其电子光谱计算结果与实验值较好地符合。  相似文献   

20.
在室温,紫外光照下溶液相中C_(60)与聚苯乙烯的直接反应合成得聚苯乙烯的 C_(60)加合物。衍生物中C_(60)的含量可由C_(60)的投料比来控制。得到了产物经 UV-Vis,FTIR,GPC,TGA及DSC等波谱表片,测得产物的分子量比母体聚苯乙烯的 分子量稍高。对溶液相的反应进行了现场的ESR研究,得到强的PSC_(60)~(-·)的 自由基信号,g值为2.0024。同时对C_(60)和聚苯乙烯混合物固相体系的光照反应 进行了ESR测试。结果表明在反应过程中及最终产物中均存在稳定的C_(60)-高分子 链烃基自由基阴离子RC_(60)~(-·)。表明了反应的自由基机理。  相似文献   

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