Multi-reference configuration interaction is used to produce potential energy curves (PECs) for the excited B1\Pi state of KH molecule. To investigate the correlation effect of core-valence electrons, five schemes are employed which include the different correlated electrons and different active spaces. The PECs are fitted into analytical potential energy functions (APEFs). The spectroscopic parameters, ro-vibrational levels, and transition frequencies are determined based on the APEFs and compared with available experimental and theoretical data. The molecular properties for B1| obtained in this letter, which are better than those available in literature, can be reproduced with calculations using the suitable correlated electrons and active space of orbitals.

A Nd:YAG pulsed laser is used to ablate HgCdTe target at different ambient pressures, the emission spectrum is detected by a time- and space-resolved diagnostic technique. It is found that the characteristics of time-resolved emission spectra are influenced by the pressure of background gas. A theoretical model is developed to investigate expansion mechanism of plasma, the time evolution of the propagation distances and the velocities of plasma plume are calculated by the model at pressures of 101000, 1000, and 5 Pa, respectively. The calculated results are well consistent with the experimental data.