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用分子图形软件设计出49种硫原子团簇Sn+(n=3~13)的结构,使用B3LYP密度泛函进行几何构型优化和振动频率计算,根据分子的总能量得出最稳定的同分异构体.在硫原子团簇正离子中,大部分原子为二配位成键.带有一、三配位的原子结构的总能量较高.部分最稳定硫原子团簇正离子的构型与最稳定的中性硫原子团簇的构型完全不同. 相似文献
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二氧化硫使品红溶液褪色是高中化学课本中的一个典型实验。从实验的角度探究了二氧化硫使碱性品红褪色的机理,另一方面,采用Gaussian 09和GaussView 5.09以及辅助量化软件Multiwfn 3.3.9计算碱性品红、SO2、HSO3-和SO32-的空间结构、电荷分布、前线轨道对称性、前线轨道能量、前线轨道各原子贡献,以及从能量角度详细探讨了二氧化硫与碱性品红褪色的机理,提出了SO2、HSO3-、SO32-使碱性品红褪色的容易程度是SO2 < HSO3- < SO32-,并呈现了二氧化硫使碱性品红溶液褪色的化学反应方程式。 相似文献
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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
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使用二次组态相互作用(QCISD)方法和6-311G(d),6-311+G(d),6-311G(2d) 及6-311+G(2d)基组研究了SO2^-和SO3^-的分子结构,超精细偶数常数(hfcc)及 其对应的分子的绝热电子亲合势(AEA)。发现在QCISD/6-311+G(2d)水平上计 算的两个分子离子的结构,hfcc值(在^33S和^17O上的)和AEA值与实验值符合得 都很好(除SO^3-中的在^33S上的hfcc值比实验值小23%)。作为比较,我们使用 相同基组作了B3LYP方法计算,得到的超精细偶合常数和AEA值却都与实验符合得不 好。 相似文献
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在UBP86/LANL2DZ和UBP86/def2-TZVP水平下详细研究了AumNin (m+n≤6)团簇的几何结构和电子性质. 详细地分析了团簇的结构特征, 平均结合能, 垂直电离势, 垂直电子亲和能, 电荷转移以及成键特征. 所有混合团簇中, 镍原子趋于聚集到一起, 形成最多Ni—Ni键, 金原子分布在镍原子聚集体周围以形成最多Au—Ni键. Ni原子较少团簇的电子性质与纯金团簇类似, 呈现一定奇偶振荡. 混合团簇中存在镍到金原子间的电荷转移. Ni原子较少团簇中, 自旋电子主要定域在Ni原子上, Ni原子较多团簇中, Au原子明显受到自旋极化. 混合团簇的分波态密度表明, AuNi混合团簇对小分子的反应活性要高于纯金团簇. 相似文献
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水簇上次氯酸与盐酸反应的理论研究 总被引:1,自引:0,他引:1
计算表明次氯酸与盐酸通过与水分子形成环状过渡态可以极大地降低反应势垒。当环上的水分子数为三时 ,势垒最小。更多的水分子通过环外的水化作用 ,使势垒进一步降低。这表明我们提出的多分子过渡态机理可以解释次氯酸与盐酸的反应由冰表面催化的实验事实 . 相似文献
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Small hydrogen-bonded water clusters have received much attention and are the subject of both theoretical and chemical research. The crystalline molecular host provides an environment for the stabilization of various topologies of water clusters. The present article deals with (H2O)
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clusters, identified/observed crystallographically in respective crystalline hydrates. The structural details of water decamers, octamers, hexamers, tetramers, and dimers are described systematically. 相似文献
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二氧化碳(CO2)和化石能源气体燃料甲烷(CH4)均是化学稳定、 温室效应较大的分子, 因而对其活化、 转化和利用的研究具有显著的理论和实际意义. 本文采用密度泛函理论方法, 计算研究了羟基氧化铟团簇与CO2, CH4和(CO2+CH4)的作用. 结果表明, 氧化铟团簇通过其活性位点—In—O(桥氧)—对CO2和CH4分子进行[2+2]加成活化, 而羟基的引入调变了氧化铟团簇活性位点上的局部电荷, 显著降低了其与CO2和CH4分子作用的活化自由能垒, 使得CO2和CH4分子的活化变得容易进行. 活性位点—In—O(桥氧)—中的In, O上的局部电荷差值(qIn-qO)越大, 其对CO2和CH4分子作用的活化自由能垒越低. 羟基氧化铟与CO2和CH4分子作用时, 电子由羟基氧化铟流向CO2和CH4分子(亲核活化); 而羟基引入前的氧化铟与CO2和CH4分子作用时, 电子则由CO2和CH4分子流向氧化铟(亲电活化). 相似文献
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二氧化硫测定过程中烟气预处理器适用范围研究 总被引:1,自引:0,他引:1
建立了一种确定二氧化硫测定过程中烟气预处理器适用范围的方法。通过使用模拟烟气检测平台,分析了使用烟气预处理器条件下,湿度和二氧化硫设定浓度变化对二氧化硫浓度测定值及二氧化硫其损失的影响,确定了二氧化硫损失率小于5%时烟气预处理器的适用范围:二氧化硫含量大于91.9 mg/m3时,湿度不大于15.1%;二氧化硫含量在33.0~91.9 mg/m3之间时,湿度不大于10.4%。该方法有助于提高二氧化硫检测和排污总量核算的准确性。 相似文献
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Wolfgang Bauer 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):493-494
Abstract A general method to reduce arene sulfonylchlorides to diarene disulfanes has been developped using sulfur dioxide and hydroiodic acid/quarternary ammonium salts as catalysts in a two - phase system. 相似文献
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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
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Xia Wu 《Journal of Cluster Science》2014,25(6):1615-1625
The geometrical symmetry presents an intriguing theoretical problem in many kinds of clusters. The diversity of geometrical structures is associated with cluster sizes, different model functions and potential parameters, and ternary clusters are investigated to study the relationship between geometrical symmetry and homotopic symmetry. Ternary Lennard-Jones model potential is studied with different parameters, and the putative global minimum structures of A13B30C12 clusters are optimized using an adaptive immune optimization algorithm. The results show that there mainly exist five geometrical symmetry structures, i.e., Mackay icosahedral, fivefold partial Mackay icosahedral, sixfold pancake, partial double Mackay icosahedral, and amorphous structures. Furthermore, the number of bonds is used to distinguish the geometrical symmetry. The importance of geometrical symmetry and homotopic symmetry determined by potential parameters is discussed. It was found that in the optimization it is more important to generate geometrical symmetry than to optimize homotopic symmetry. 相似文献
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The geometries, stabilities, electronic, and magnetic properties of hydrogen adsorption on Ru
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clusters have been systematically investigated by using density functional theory with generalized gradient approximation.
The result indicates the absorbed species does not lead to a rearrangement of the basic cluster. For n > 2, three different adsorption patterns are found for the Ru
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H2 complexes: One H atom binds to the Ru top site, and another H binds to the bridge site for n = 3, 5, 6, 8; bridge site adsorption for n = 4; hollow site and top site adsorption for n = 7. The adsorption energies display oscillation and reach the peak at n = 2, 4, 7, implying their high chemical reactivity. The small electron transferred number between H atoms and Ru
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clusters indicates that the interaction between H atoms and Ru
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clusters is small. When H2 is absorbed on the Ru
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clusters, the chemical activity of corresponding clusters is dramatically increased. The absorbed H2 can lead to an oscillatory behavior of the magnetic moments, and this behavior is rooted in the electronic structure of the
preceding cluster and the changes in the magnetic moment are indicative of the relative ordering of the majority and minority
LUMO’s. The second order difference indicates 5 is magic number in Ru
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H2 and Ru
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clusters. 相似文献
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