CAJ | 학술논문

采用内收缩多参考组态相互作用( MRCI)方法结合相关一致基aug-cc-pV5Z计算了CP分子X2Σ+,A2Π和B2Σ+和CP-离子X1Σ+电子态的势能曲线。考虑了Davidson、相对论和核价相关修正对势能曲线的影响。本文的相对论修正是利用二阶Douglas-Kroll 哈密顿近似在cc-pV5Z基组水平进行的；同时核价相关修正也是在cc-pV5Z基组水平进行的。为了提高计算精度,利用基组外推将能量外推至完全基组极限处,得到外推的势能曲线。对这些势能曲线进行拟合,得到各种水平下四个电子态的光谱常数( Te , Re ,ωe ,ωe xe ,αe 和Be ),并详细分析了Davidson修正、相对论修正和核价相关修正及基组外推对光谱常数的影响。与其它理论结果和实验数据进行比较,可知本文的结果更精确、更完整。
채용내수축다삼고조태상호작용( MRCI)방법결합상관일치기aug-cc-pV5Z계산료CP분자X2Σ+,A2Π화B2Σ+화CP-리자X1Σ+전자태적세능곡선。고필료Davidson、상대론화핵개상관수정대세능곡선적영향。본문적상대론수정시이용이계Douglas-Kroll 합밀돈근사재cc-pV5Z기조수평진행적；동시핵개상관수정야시재cc-pV5Z기조수평진행적。위료제고계산정도,이용기조외추장능량외추지완전기조겁한처,득도외추적세능곡선。대저사세능곡선진행의합,득도각충수평하사개전자태적광보상수( Te , Re ,ωe ,ωe xe ,αe 화Be ),병상세분석료Davidson수정、상대론수정화핵개상관수정급기조외추대광보상수적영향。여기타이론결과화실험수거진행비교,가지본문적결과경정학、경완정。
The full valence complete active space self-consistent field ( CASSCF) method followed by the high-ly accurate valence internally contracted multireference configuration interaction ( MRCI) approach has been em-ployed to investigate the potential energy curves ( PECs) for X2Σ+, A2Πand B2Σ+ of CP and X1Σ+ electronic states of CP-. In the present calculations, the basis sets used are correlation-consistent basis sets, aug-cc-pV5Z. The PECs determined by the MRCI calculations are corrected for size-extensivity errors by means of the Davidson modification ( MRCI+Q). To obtain more reliable results, effects on the PECs by the core-valence correlation and relativistic corrections are taken into account. The core-valence correlation correction is carried out with the cc-pV5Z basis set. The way to consider the relativistic correction is to use the second-order Doug-las-Kroll Hamiltonian (DKH2) approximation, and the correction is performed at the level of cc-pV5Z basis set. Then the PECs of electronic states involved are extrapolated to the complete basis set limit. With the PECs, the spectroscopic parameters (Te, Re, ωe, ωexe, ωeye, αe and Be) of these three electronic states are deter-mined and compared in detail with those reported in the literature. Comparison with the experimental data shows that the present spectroscopic parameters are more accurate than the previous calculations.