A Coulomb-related family of potentials having zero-energy bound states

We propose here a new large class of singular central potentials having zero-energy bound states for many values of angular momenta. The potentials are shown to be closely related to the standard attractive Coulomb interaction. Some of them admit the E≠0$E\ne 0$ bound states as well. A quantum–classical correspondence is also discussed.     

Calculations of dynamic dipole polarizabilities of Li and Na atoms in debye plasma using the model potential technique

The effects of Debye plasma on the frequency‐dependent polarizabilities of Li and Na atoms are investigated using symplectic algorithm within the framework of the pseudostate summation technique. Dynamic dipole polarizabilities of Li (2s ²S) and Na(3s ²S) as functions of scaled number density of the plasma electrons for arbitrary plasma temperature are presented. Screening effects on the resonance frequencies are also presented. In free‐atomic cases, our calculated results are comparable with the reported theoretical and experimental predictions. © 2012 Wiley Periodicals, Inc.     

Phenylethenyl‐Substituted Triphenylamines: Efficient,Easily Obtainable,and Inexpensive Hole‐Transporting Materials

Star‐shaped charge‐transporting materials with a triphenylamine (TPA) core and various phenylethenyl side arm(s) were obtained in a one‐step synthetic procedure from commercially available and relatively inexpensive starting materials. Crystallinity, glass‐transition temperature, size of the π‐conjugated system, energy levels, and the way molecules pack in the solid state can be significantly influenced by variation of the structure of these side arm(s). An increase in the number of phenylethenyl side arms was found to hinder intramolecular motions of the TPA core, and thereby provide significant enhancement of the fluorescence quantum yield of the TPA derivatives in solution. On the other hand, a larger number of side arms facilitated exciton migration through the dense side‐arm network formed in the solid state and, thus, considerably reduces fluorescence efficiency by migration‐assisted nonradiative relaxation. This dense network enables charges to move more rapidly through the hole‐transport material layer, which results in very good charge drift mobility (μ up to 0.017 cm² V ^?1 s^?1).     

icMRCI+Q理论研究CF离子12个-S态和23个?态的光谱性质

采用考虑Davidson修正的内收缩多参考组态相互作用(icMRCI+Q)方法结合相关一致基组aug-ccpV5Z和aug-cc-pV6Z计算了CF~+离子第一离解极限C~+(~2p_u)+F(~2P_u)对应的12个∧-S态(X~l∑~+,a~3∏,1~3∑~+,1~3Δ,1~1∑~-,1~1∑~-,1~3∑~-,2~1∑~+,1~1∏,2~3∏,2~1∏和2~3∑~+)所产生的23个Ω态的势能曲线.计算中考虑了旋轨耦合效应、核价相关和标量相对论修正以及将参考能和相关能分别外推至完全基组极限.基于得到的势能曲线,获得了束缚和准束缚的9个∧-S态和16个Ω态的光谱常数,并且X~1∑~+,a~3∏~(势阱一)∧-S态的光谱常数与已有的实验结果非常符合.此外,计算了CF自由基X~2∏态到CF~+离子束缚和准束缚的9个∧-S态的垂直电离势和绝热电离势,并且CF~+(X~1∑~+)←CF(X~2∏)和CF~+(a~3∏(势阱一))←CF(X~2∏)的垂直电离势和绝热电离势与相应的实验结果也非常符合.由a~3∏,1~1∏态和其他激发∧-S态势能曲线的交叉现象,借助于计算的旋轨耦合矩阵元,分析了a~3∏~(势阱一),1~1∏~(势阱一)和2~1∑~+态的预解离机理.计算的23个Ω态离解极限处的相对能量与实验结果十分吻合.最后计算了(2)0+~(势阱一)(v'=0-5),(1)1~(势阱一)(v'=0-5)和(2)1~(势阱一)(v'=0)到X0~+态跃迁的Franck-Condon因子和辐射寿命.     

Photoionization and Pyrolysis of a 1,4‐Azaborinine: Retro‐Hydroboration in the Cation and Identification of Novel Organoboron Ring Systems

The photoionization and dissociative photoionization of 1,4‐di‐tert‐butyl‐1,4‐azaborinine by means of synchrotron radiation and threshold photoelectron photoion coincidence spectroscopy is reported. The ionization energy of the compound was determined to be 7.89 eV. Several low‐lying electronically excited states in the cation were identified. The various pathways for dissociative photoionization were modeled by statistical theory, and appearance energies AE_0K were obtained. The loss of isobutene in a retro‐hydroboration reaction is the dominant pathway, which proceeds with a reverse barrier. Pyrolysis of the parent compound in a chemical reactor leads to the generation of several yet unobserved boron compounds. The ionization energies of the C₄H₆BN isomers 1,2‐ and 1,4‐dihydro‐1,4‐azaborinine and the C₃H₆BN isomer 1,2‐dihydro‐1,3‐azaborole were determined from threshold photoelectron spectra.     

线性响应和两种态特定方法模拟AF350电子跃迁的溶剂效应

在极化连续模型框架下比较了线性响应与两种不同态特定方法计算的溶液中Alexa Fluor 350(AF350)分子激发能和光谱移动值的差异. AF350的第一激发态S0→S1电子跃迁属于π→π^*跃迁, 主要对应于最高占据分子轨道(HOMO)到最低空轨道(LUMO)的跃迁. 该分子激发态偶极矩大于基态偶极矩, 激发态时溶质溶剂相互作用比基态时更强, 随着溶剂极性增大, 会发生光谱红移的现象. 与实验值相比, 线性响应和两种态特定方法均高估了激发能, 其中以IBSF(Improta-Barone-Scalmani-Frisch)方法得到的激发能最小, 矫正的基态反应场方法(cGSRF)得到的激发能最大. 对于光谱移动值, 3种方法与实验值相比都偏小, 线性响应方法(LR)计算出的误差最大, 而IBSF方法得到的结果与实验值最吻合, 是预测溶液中AF350分子激发能和光谱移动值最准确的方法. 对比了Marcus传统理论和基于约束平衡的非平衡溶剂化理论的结果, 发现后者得到的激发能和光谱移动值更接近于实验值.     

Physicochemical assessment of prednisone adsorption on two molecular composites using statistical physics formalism in cosmetics

In this paper, we consider two different polyethylene filter plates coated with multi-walled carbon nanotubes (MWCNTs) and synthesized by surface molecularly imprinted technique, namely plate@MWCNTs@MIPs (PMIPs) and plate@MWCNTs@NIPs (PNIPs). They were used as effective adsorbents for selective adsorption and detection of prednisone (PS) in cosmetics. As a first assessment to investigate the performance of these adsorbents, the PS adsorption isotherms were analyzed using an advanced multilayer statistical physics model at three different temperatures ( 293, 303 and 313 K) and over a wide PS concentration range (0.09–1.5 mg/mL). The obtained analyzing results from the best fitting model showed that the PMIPs adsorbent displayed a high adsorption capacity (27.4 mg/g) due to the contribution of the number of PS molecules per site (n_m) combined with the receptor sites density (D_m), which displayed a high recognition ability due to the adsorption energy. Modeling analysis process indicated that the PS molecules could be anchored on the PMIPs and PNIPs surfaces via a non-parallel orientation where the adsorption is a multi-molecular process. The calculated adsorption energies globally varied from 4.51 to 7.62 kJ/mol, confirming the physical nature of the adsorption process for the studied systems, which is beneficial in cosmetics. Finally, three thermodynamic potentials (entropy, internal energy and free enthalpy) were evaluated for a better understanding of the physico-chemical behavior of the adsorption process.