The coupled cluster calculations with accounting for relativistic effects to study spectroscopic and chemical properties of element 120 (E120) are performed. Similar calculations for Ba are also done and they are in a good agreement with the experimental data. Dissociation energies of diatomic X-H and X-Au molecules, where X=E120, Ba, are calculated; for E120 they are found to be $1.5\div2$ times smaller than those for Ba.
The generalized relativistic effective core potential calculations of the adiabatic potential curve and spectroscopic constants for the ground electronic state of the Ca2
Relativistic ab initio study on the spectroscopic and radiative properties of the lowest states and modeling of the optical cycles for the LiFr molecule
Chemical bond analysis for the entire periodic table: Energy Decomposition and Natural Orbitals for Chemical Valence in the Four-Component Relativistic Framework
A fully {\it ab initio} potential curve of near-spectroscopic quality for the OH^- anion: importance of connected quadruple excitations and scalar relativistic effects
对羟基阴离子OH ^{-}的基态电势曲线进行了基准研究,包括1粒子和n粒子基组的详细校准。CCSD(T)基组极限高估了$ω_e$约10 cm ^{-1},这只能通过在耦合团簇展开中包含连接的四重激发--或者等效地,在多参考计算的有效空间中包含$2π$轨道来补救。在包含标量相对论效应($ω_e$上的~3 cm ^{-1})后,获得光谱质量(亚cm ^{-1}精度)的势曲线。我们最好的计算EA(OH),1.828 eV,同意小数点后三位的最佳实验值。我们计算的最佳离解能D_0(OH ^-)= 4.7796 eV和D_0(OH)= 4.4124 eV表明实验D_0(OH)= 4.392 eV可能偏低了0.02 eV。
The Fundamental Vibrational Frequencies and Spectroscopic Constants of the Dicyanoamine Anion, NCNCN$^-$ (C$_2$N$_3^-$): Quantum Chemical Analysis for Astrophysical and Planetary Environments
探测空间阴离子依赖于理论分析和实验室分析之间的密切合作,以高精度测量旋转光谱和光谱常数。以更高精度和更低计算成本运行的改进的量子化学工具的出现是对天体物理相关阴离子的基本表征及其在星际介质和行星大气中的检测的关键解决方案。在这种情况下,我们已经转向五原子二氰基胺阴离子NCNCN $^-$(C $_2$ N $_3^-$),结构弯曲和极性化合物的量子化学分析。我们已经进行了高层次的耦合集团理论四次力场(QFF)计算的C $_2$ N $_3^-$满足计算成本和精度的条件。我们提供了第一次准确的光谱常数和振动频率为这个离子。除了表现出各种费米共振外,C $_2$ N $_3^-$还显示出明亮的$ν$ 2(2130.9 cm $^{-1}$)和不太强烈的$ν$ 1(2190.7 cm $^{-1}$)基本振动频率,为未来红外观测< 5 $μ$ m提供了强有力的标志。我们还确定了明亮基频的近红外泛音和组合带,其中4312.1 cm $^{-1}$(2.319 $μ$ m)处的2 $ν$ 2是最佳候选者。C $_2$ N $_3^-$可能存在于ISM的富氮环境中,如IRC +10216和其他富碳的拱星包层,或者在土星的卫星土卫六的大气中,在那里先进的N基反应可能导致它的形成。