搜索结果: 46-60 共查到“知识库 化学物理学”相关记录378条 . 查询时间(3.195 秒)
Conjugation in hydrogen-bonded systems
molecular clusters electron density distribution hydrogen bonds conjugation cooperativity
2012/4/19
Analysis of the electron density distribution in clusters composed of hydrogen fluoride, water, and ammonia molecules, especially within the hydrogen-bond domains, reveals the existence of both \sigma...
Role of quantum nuclei and local fields in the x-ray absorption spectra of water and ice
Role of quantum nuclei local fields the x-ray absorption spectra of water and ice Chemical Physics
2012/4/19
We calculate the x-ray absorption spectra of liquid water at ambient conditions and of hexagonal ice close to melting, using a static GW approach that includes approximately local field effects. Quant...
溶液中金纳米棒形成过程的光谱动力学分析
金纳米棒 生长机制 电荷转移
2012/5/4
通过动态光谱跟踪溶液中金纳米棒的尺度和长径比(AR)的变化，成功地获取粒子的生长过程的动态数据. 该过程分为两步：种子快速形成棒状粒子；棒状粒子在一定AR下的生长. 通过分析体系中的一价金、金粒子和抗坏血酸之间的电荷转移过程，建立了金纳米棒生长过程的电荷转移模型，并很好地解释了动态光谱的实验数据.
通过将相转化法制备的Ni-BaZr0.1Ce0.7Y0.2O3-δ(BZCY)纤维膜生坯在5%H2/95%Ar混合气体中直接烧结， 制备出了气密具有“三明治”结构的Ni-BZCY金属陶瓷中空纤维膜. 靠近内外表面是指状孔结构而中间部分是致密层. 当膜管外湿润的20%H2/80%N2混合气体流量是200 mL/min，膜管内高纯Ar气的流量是150 mL/min时，Ni-BZCY中空纤维膜的氢渗透率...
Is the aether entrained by the motion of celestial bodies? What do the experiments tell us?
aether the motion of celestial bodies experiments General Physics
2012/4/20
Even though the concept has evolved and if the designation as aether is improperly regarded as outdated, nobody today considers that the vacuum is empty. However, the nature and the properties of the ...
甲醇在Pt (100)表面吸附与解离的第一性原理研究
甲醇 Pt(100)表面 吸附 解离
2012/5/4
采用基于第一性原理的密度泛函理论结合周期模型方法对甲醇在Pt(100)完整表面的吸附与解离进行了研究. 通过比较不同吸附位置的吸附能与构型参数发现，表面top吸附位为最稳定吸附位，甲醇分子通过氧原子吸附于Pt(100)表面. 同时计算了甲醇分子在top吸附位可能的解离路径，发现在解离过程中OH键首先断裂的路径为最低能量路径. 分解生成的若干产物其吸附稳定性排序为CH3O>CH2OH>CH3>CH2...
Cu原子掺杂在Al团簇中的结构和电子性质
密度泛函理论 电子性质 Cu原子掺杂Al团簇
2012/5/4
利用密度泛函理论，对Aln(n=1～15)团簇中掺杂Cu原子后的双金属团簇进行了研究，在结构优化的基础上，同时计算了双金属团簇的电子性质，即电子亲和能、电离势、Cu原子的Mulliken分布、平均极化率、极化率的各向异性、偶极矩及HOMO-LUMO能隙随团簇尺寸增加时的变化情况. 结果表明，Cu掺杂Al团簇的双金属团簇中也存在幻数结构，团簇的电子性质随团簇尺寸大小出现不规则的奇偶振荡变化. n=1...
Dynamic clustering in active colloidal suspensions with chemical signaling
Dynamic cluster active colloidal suspensions chemical signaling
2012/2/29
In this paper, we explore experimentally the phase behavior of a dense active suspension of self- propelled colloids. In addition to a solid-like and a gas-like phase observed for high and low densiti...
SAC-CI Calculation of a Series of the Lowest 2-Pi-States of HCl+ and HBr+ Ions
diatomic molecule potential curves HCl+, HBr+ SAC-CI method
2012/2/29
The symmetry-adapted-cluster configuration interaction (SAC-CI) method is used for ab initio calculation of electronic structure of HCl+ and HBr+ molecular ions. Potential energy curves (PEC) are obta...
Error analysis of free probability approximations to the density of states of disordered systems
Massachusetts Institute of Technology
2012/2/29
Theoretical studies of localization, anomalous diffusion and ergodicity breaking require solving the electronic structure of disordered systems. We use free probability to approximate the ensemble- av...
Breaking the Mode Degeneracy of Surface-Plasmon Resonances in a Triangular System
Breaking Mode Degeneracy Surface-Plasmon Resonances Triangular System
2012/2/29
In this paper, we present a systematic investigation of symmetry-breaking in the plasmonic modes of triangular gold nanoprisms. Their geometrical C3 symmetry is one of the simplest possible that allow...
Entropy-Enthalpy Compensation May Be a Useful Interpretation Tool for Complex Systems Like Protein-DNA Complexes: An Appeal to Experimentalists
Entropy-Enthalpy Compensation Useful Interpretation Tool Complex Systems Like Protein-DNA Complexes Experimentalists
2012/2/29
In various chemical systems enthalpy-entropy compensation (EEC) is a well-known rule of behavior, although the physical roots of it are still not completely understood. It has been frequently question...
Exciton transport in thin-film cyanine dye J-aggregates
Exciton transport thin-film cyanine dye J-aggregates
2012/2/29
We present a theoretical model for the study of exciton dynamics in J-aggregated monolayers of fluorescent dyes. The excitonic evolution is described by a Monte-Carlo wave function approach which allo...
Effect of discontinuities in Kohn-Sham-based chemical reactivity theory
Effect of discontinuities Kohn-Sham-based chemical reactivity theory Fukui function
2012/2/29
We provide a new derivation of a formula for the Fukui function of density-functional chemical reactivity theory which incorporates the discontinuities in the Kohn-Sham reference system. Orbital relax...
Multiscale QM/MM Molecular Dynamics Study on the First Steps of Guanine-Damage by Free Hydroxyl Radicals in Solution
Multiscale QM/MM Molecular Dynamics Study First Steps Guanine-Damage Free Hydroxyl Radicals Solution
2012/2/29
Understanding the damage of DNA bases from hydrogen abstraction by free OH radicals is of particular importance to reveal the effect of hydroxyl radicals produced by the secondary effect of radiation....