DFT(B3LYP, B3PW91) level calculations in conjunction with three different of basis sets have been used to investigate the variations in the bond lengths, dipole moment and rotational constants, IR frequencies, IR intensities and rotational invariants of ClCCCN. The nuclear quadrupole constants of chlorine and nitrogen of ClCCCN have been calculated on the experimental r$_{s}$ structure as well as on the B3PW91/6-311++g(d,p) optimized geometry and are found to be within the scale length of the experimental uncertainty. The slopes and intercepts obtained from the regression analysis between the B3LYP/6-311++g(d,p) level calculated and experimental B$_{o}$ values of ClCCCN were used to calculate the reasonable values of rotational constants of all the rare isotopic species of ClCCCN having standard deviation $\pm$0.048 MHz. All the spectroscopic parameters obtained from DFT calculation shows satisfactory agreement with the available experimental data.
On the universality of spectroscopic constants of diatomic molecules
我们通过机器学习的方法，证明了双原子分子的平衡距离，谐波振动频率和结合能是普遍相关的。特别是，光谱常数之间的关系是有效的独立的分子键。然而，它们强烈地依赖于组成原子的基团和周期。结果表明，利用分子内原子的基团和周期，可以预测光谱常数，其精度为$\lesssim 5\%$。最后，当采用{ \it ab initio}和密度泛函理论（DFT）电子结构方法的光谱常数时，满足相同的普适关系。
How Good Is DFT for Solid-Liquid Interfaces? A Comparison With the Random-Phase Approximation for Water on Graphene
University of Cambridge（剑桥大学）；Max Planck Institute for Polymer Research（马克斯·普朗克聚合物研究所）；Max Planck Initiative for Liquid Research（马克斯·普朗克液体研究倡议）；Universitat Politècnica de Catalunya（加泰罗尼亚理工大学）
Triplet-Tuning: A Novel Family of Non-Empirical Exchange-Correlation Functionals
In the framework of DFT, the lowest triplet excited state , T $_1$ , can be evaluated using multiple formulations, the most straightforward of which are UDFT and TDDFT. Assuming the exact XC functional is applied, UDFT and TDDFT provide identical energies for T $_1$ ( $E_{\rm T}$ ), which is also a constraint that we require our XC functionals to obey. However, this condition is not satisfied by most of the popular XC functionals, leading to inaccurate predictions of low-lying, spectroscopically and photochemically important excited states , such as T $_1$ and S $_1$ . Inspired by the optimal …
Theoretical Study of C36 and O@C36 Fullerene Isomers with (C1, C2, Cs, D2, D3h) symmetries: Geometry Optimization, Electrical Properties and Spectroscopic Analysis
