共查询到20条相似文献,搜索用时 109 毫秒
1.
DIELECTRONICRECOMBINATIONRATECOEFFICIENTSFORNEONLIKEIONSDIELECTRONICRECOMBINATIONRATECOEFFICIENTSFORNEONLIKEIONS¥ZhaoLibo;LiS... 相似文献
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EFFECTOFRADIALELECTRICALFIELDONNEOCLASSICALTRANSPORTINTOKAMAKSEFFECTOFRADIALELECTRICALFIELDONNEOCLASSICALTRANSPORTINTOKAMAKS¥... 相似文献
3.
《原子与分子物理学报》1996,(3)
THEREFLECTIVITYCALIBRATIONANDAPPLICATIONOFXRAYGRAZINGMIRRORMaHongliangSunKexuYiRongqingCuiYanliZhengZhijianTangDaoyuanSouthw... 相似文献
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《原子与分子物理学报》1996,(4)
DYNAMICDESCRIPTIONOFIONCLOUDINRFTRAPManBaoyuan1WangXiangtai2HuXierong1ZhuJunkong21DepartmentofOpticsofShandongUniversityJina... 相似文献
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RELATIVISTICCALCULATIONOFIONIZATIONENERGIESFORTITANIUMIONSTiⅠTOTiChenBo1,2TanMingliang2JiangGang2ZhuZhenghe2ZhaoYongkuan31In... 相似文献
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Chen Zhangjin a b Xu Kezun b Xu Fuxin aa Department of Physics Anhui Unviersity Hefei b Department of Modern Physics University of Science Technology of China Hefei 《原子与分子物理学报》1998,(3)
LOWENERGYTRIPLEDIFFERENTIALCROSSSECTIONSFORELECTRONIMPACTIONIZATIONOFHYDROGENChenZhangjina,bXuKezunbXuFuxinaaDepartmentofPhy... 相似文献
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Li Taihua An Zhu Luo Zhengming Center for Radiation Physics Institute of Nuclear Science Technology Sichuan Union University Chengdu 《原子与分子物理学报》1997,(1)
MEASUREMENTSOFFeANDCuK-ShelIONIZATIONCROSSSECTIONSBYSLOWELECTRONIMPACTLiTaihuaAnZhuLuoZhengmingCenterforRadiationPhysics,Ins... 相似文献
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Pang Xiaofeng International Centre for Material Physics Academia Sinica Dept. of Physics Southwest Institute for Nationalities The Institue of Atomic Molecular Physics Sichuan Union UniversityShenyang Chengdu Chengdu 《原子与分子物理学报》1997,(1)
ASTATISTICALTHEORYFORTHEBIO-PHOTONEMISSIONOFTHELIVINGSYSTEMSPangXiaofengInternationalCentreforMaterialPhysics,AcademiaSinicaD... 相似文献
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THEORETICALCALCULATIONOFATOMICANDMOLECULARDATAPeiChunchuanPurpleMountainObservatoryAcademiaSinicaNanjing210008ABSTRACTByusin... 相似文献
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THEMACQMCALCULATIONOFTHETOTALENERGYCURVEFORTHEICOSAHEDRALCENTRALSTRUCTUREOFTHECLUSTERH-13ZhangJianping*LiPingGouQingquanInst... 相似文献
11.
基于极性叠加原理,在成功设计烷烃异构体和多氯代烷烃生成焓计算新方法的基础上,设计了一种计算多元醇异构体生成焓的新方法,并合理地假定任一异构体的原子化焓等于三种键(C-C、C-H和C-O-H键)的键能、极性叠加能项以及氢键能项的加和。用这一模型拟合24种原子化粹数据,得到了标准生成焓的估算公式。为了检验预测的精确性,又设计了一种预测方法,使用在排除液预测的化合物条件下回归得到的参数,预测该化合物的生成焓。按这种方法,预测了24种异构体的生成焓。通过该5参数预测的相对于实验值的各种误差(平均绝对误差、均方根误差和最大绝对误差)不仅比7参数的基团法预测的对应误差小得多,而且比相应实验数据的误差还要小。与键加和法比较,该方法的模型包含了极性叠加能和氢键能量,该两项代表了主要的非键相互作用能,表征了不同异构体的结构差异,并大大减少了参数。 相似文献
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The standard molar enthalpies of combustion, sublimation, and formation of three nitrogen-containing heterocycles, namely, 2-benzimidazolinone, 2-benzoxazolinone and 3-indazolinone were determined calorimetrically. The standard (p°?=?0.1?MPa) molar enthalpies of formation in the gas phase were derived from the standard molar enthalpies of combustion, in oxygen, at T?=?298.15?K, measured by static bomb combustion calorimetry and from the standard molar enthalpies of sublimation at T?=?298.15?K, measured by Calvet microcalorimetry. Møller–Plesset calculations at the MP2 level and density functional calculations with the B3LYP functional and extended basis sets were also performed to determine the energetically preferred tautomeric form of the molecules. The results were qualitatively independent of the calculational level, where in general the DFT calculations were in better agreement with experiment than those from MP2. The gas and solid phase enthalpic differences between imines and amides, wherein –CH=N- is contrasted with –CONH-, have been studied and roughly constant values have been found. 相似文献
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本文讨论了利用计算机模拟技术研究传能产物振动布层的理论和方法。以Ar(^3P0.2)+PCl3反应生成PCl(A^3П)为例,对模拟的过程和其中应注意的问题进行了分析。文中首次报道了PCl(A^3П→X^3Σ^-1)跃迁的Franck-Condon因子。 相似文献
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Suitable theoretical methods are validated for organosulfur compounds using experimental data for gas phase enthalpies of formation, proton affinities (PA) and heterolytic bond dissociation enthalpies (HBDEs). From enthalpies of chloride anion transfers from neutral chlorides to acyl, sulfonyl or cumyl cations in the gas phase, it is calculated that (i) similar aromatic substituent effects are expected for heterolyses of acyl, sulfonyl and cumyl chlorides; (ii) HBDEs for loss of chloride increase by over 70 kcal mol?1 from 4‐MeOC6H4COCl to SO2Cl2. Rate constants for solvolyses of 4‐Z‐substituted arenesulfonyl chlorides (Z = OMe, Me, H, Cl, NO2) in 97% w/w 2,2,2‐trifluoroethanol (TFE)–water are reported. Substituent effects are smaller than observed for identical solvolyses of acyl and cumyl chlorides, and are much smaller than those predicted theoretically for gas phase unimolecular heterolysis (explained by variable amounts of nucleophilic solvent assistance). Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
15.
José R. B. Gomes Emanuel A. Sousa Jorge M. Gonçalves Luís Gales Ana M. Damas Paula Gomes Siddharth Pandey William E. Acree Jr Maria D. M. C. Ribeiro da Silva 《Journal of Physical Organic Chemistry》2007,20(7):491-498
The gaseous standard molar enthalpies of formation of two 2‐R‐3‐methylquinoxaline‐1,4‐dioxides (R = benzoyl or tert‐butoxycarbonyl), at T = 298.15 K, were derived using the values for the enthalpies of formation of the compounds in the condensed phase, measured by static bomb combustion calorimetry, and for the enthalpies of sublimation, measured by Knudsen effusion, using a quartz crystal oscillator. The three dimensional structure of 2‐tert‐butoxycarbonyl‐3‐methylquinoxaline‐1,4‐dioxide has been obtained by X‐ray crystallography showing that the two N? O bond lengths in this compound are identical. The experimentally determined geometry in the crystal is similar to that obtained in the gas‐phase after computations performed at the B3LYP/6‐311 + G(2d,2p) level of theory. The experimental and computational results reported allow to extend the discussion about the influence of the molecular structure on the dissociation enthalpy of the N? O bonds for quinoxaline 1,4‐dioxide derivatives. As found previously, similar N? O bond lengths in quinoxaline‐1,4‐dioxide compounds are not linked with N? O bonds having the same strength. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Maria Victoria Roux Manuel Temprado Rafael Notario ? Sergey P. Verevkin ? Vladimir N. Emel'yanenko Douglas E. Demasters 《Molecular physics》2013,111(18):1909-1917
Phenylacetic acid and the isomeric 1- and 2-naphthylacetic acids are at the confluence of diverse concepts, techniques and classes of organic compounds. Summing the results of our new enthalpy of formation of the gaseous phenylacetic acid reported herein, and of literature enthalpy of formation of the isomeric solid naphthylacetic acids and of our new sublimation enthalpies reported herein, we derive gas phase enthalpies of formation of ?314.7±3.1, ?246.9±2.0 and ?247.4±2.1kJmol?1 respectively. This corresponds to 1- and 2-naphthylacetic acid having indistinguishable enthalpies of formation. We also performed MP2(full)/6-31G(d) calculations on these species, resulting in enthalpies of formation of ?307.3±0.8, ?247.4±3.4 and ?247.5±3.4kJmol?1 for phenylacetic acid and 1- and 2-naphthylacetic acid in satisfactory agreement with the above experimental results. 相似文献
18.
Gas‐phase equilibrium constants for the thermally initiated oxidation of hexafluoropropene with molecular oxygen 下载免费PDF全文
David Lokhat Deresh Ramjugernath Maciej Starzak 《Journal of Physical Organic Chemistry》2015,28(7):460-471
Equilibrium constants for a kinetic model of the thermally initiated gas‐phase oxidation of hexafluoropropene have been calculated in the temperature range of 463–493 K based on the thermochemical properties of the reactive species. Standard molar enthalpies and entropies of formation as well as heat capacities of trifluoroacetyl fluoride, hexafluorocyclopropane, hexafluoropropene, and hexafluoropropene oxide were predicted using methods of quantum statistical mechanics. These along with literature data for remaining species involved allowed for calculating reaction enthalpies of individual steps of the proposed reaction mechanism. The calculations were performed at the G4 B3LYP/6‐31G(2df,p) level of theory. The enthalpy of formation was determined using both the atomization method and isodesmic reaction schemes. All reactions apart from the decomposition of hexafluoropropene oxide were found to be exothermic. Only the hexafluoropropene oxide decomposition reaction was found to be noticeably reversible under the reaction conditions considered. This was confirmed through independent experimentation and kinetic model identification. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
19.
Activity coefficients for cyclohexanol in diluted isooctane solutions at 25°C and 45°C are obtained from vapour pressure measurements, xu = 10?3 to 5.10?2 (xu mole fraction of cyclohexanol) ; enthalpies of mixing for the same composition range are obtained at 25°C. The results are interpreted in terms of the model of ideal association where open dimer and trimer, open and cyclic other i-mers are considered in a six parameters model : two standard enthalpies for formation of the H-bonds (Δ2o for the dimer and h for the stepwise formation for other bonds), four equilibrium constants (K2o and K3o for the dimer and trimer formation from the monomer, Kc for the cyclisation of an open i-mer and k for the stepwise formation of an open, or cyclic, i-mer higher than the trimer). The cyclic form of the tetramer is shown to be the predominent one. 相似文献