{"title":"韦斯特菲特自旋扭转光谱新程序","authors":"","doi":"10.1016/j.jms.2024.111928","DOIUrl":null,"url":null,"abstract":"<div><p>A new program, <span>westerfit</span>, has been developed to treat <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span> molecules with internal rotation and spin angular momentum. It implements a single diagonalization Rho Axis Method approach for the torsion–rotation alongside a complete treatment of nuclear quadrupole interaction and spin–rotation coupling. Unlike other programs designed for internal rotation with spin effects, <span>westerfit</span> includes matrix elements off-diagonal in the rotational angular momentum quantum number, <span><math><mi>N</mi></math></span>, rather than the perturbative treatment of the spin–rotation and quadrupole interactions. This full combined approach allows fitting of all symmetrically allowed terms in both the spin–rotation and the quadrupole tensors as well as inclusion of higher order terms coupling the large amplitude motion to the spin angular momentum. The program was benchmarked against other published programs to test molecular cases of torsion–rotation, spin–rotation, and spin–torsion-rotation. All three tests produced a lower RMS. <span>westerfit</span> paves a way forward for complete treatment of spin–torsion–rotation problems regardless of barrier height or quadrupole moment.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":1.4000,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"westerfit: A new program for spin–torsion–rotation spectra\",\"authors\":\"\",\"doi\":\"10.1016/j.jms.2024.111928\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>A new program, <span>westerfit</span>, has been developed to treat <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>s</mi></mrow></msub></math></span> molecules with internal rotation and spin angular momentum. It implements a single diagonalization Rho Axis Method approach for the torsion–rotation alongside a complete treatment of nuclear quadrupole interaction and spin–rotation coupling. Unlike other programs designed for internal rotation with spin effects, <span>westerfit</span> includes matrix elements off-diagonal in the rotational angular momentum quantum number, <span><math><mi>N</mi></math></span>, rather than the perturbative treatment of the spin–rotation and quadrupole interactions. This full combined approach allows fitting of all symmetrically allowed terms in both the spin–rotation and the quadrupole tensors as well as inclusion of higher order terms coupling the large amplitude motion to the spin angular momentum. The program was benchmarked against other published programs to test molecular cases of torsion–rotation, spin–rotation, and spin–torsion-rotation. All three tests produced a lower RMS. <span>westerfit</span> paves a way forward for complete treatment of spin–torsion–rotation problems regardless of barrier height or quadrupole moment.</p></div>\",\"PeriodicalId\":16367,\"journal\":{\"name\":\"Journal of Molecular Spectroscopy\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.4000,\"publicationDate\":\"2024-07-17\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Molecular Spectroscopy\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022285224000559\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"PHYSICS, ATOMIC, MOLECULAR & CHEMICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Molecular Spectroscopy","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022285224000559","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PHYSICS, ATOMIC, MOLECULAR & CHEMICAL","Score":null,"Total":0}
引用次数: 0
摘要
我们开发了一个新程序 westerfit,用于处理具有内旋转和自旋角动量的铯分子。它采用单一对角化 Rho 轴法处理扭转-旋转,同时对核四极相互作用和自旋-旋转耦合进行了全面处理。与其他针对带有自旋效应的内旋转设计的程序不同,westerfit 包含了旋转角动量量子数 N 对角线外的矩阵元素,而不是自旋旋转和四极相互作用的扰动处理。这种完全结合的方法可以拟合自旋旋转和四极张量中所有对称允许的项,并包含将大振幅运动与自旋角动量耦合的高阶项。该程序与其他已发布的程序进行了基准测试,测试了扭转旋转、自旋旋转和自旋-扭转旋转的分子情况。westerfit 为完整处理自旋-扭转-旋转问题铺平了道路,而不受阻挡高度或四极矩的影响。
westerfit: A new program for spin–torsion–rotation spectra
A new program, westerfit, has been developed to treat molecules with internal rotation and spin angular momentum. It implements a single diagonalization Rho Axis Method approach for the torsion–rotation alongside a complete treatment of nuclear quadrupole interaction and spin–rotation coupling. Unlike other programs designed for internal rotation with spin effects, westerfit includes matrix elements off-diagonal in the rotational angular momentum quantum number, , rather than the perturbative treatment of the spin–rotation and quadrupole interactions. This full combined approach allows fitting of all symmetrically allowed terms in both the spin–rotation and the quadrupole tensors as well as inclusion of higher order terms coupling the large amplitude motion to the spin angular momentum. The program was benchmarked against other published programs to test molecular cases of torsion–rotation, spin–rotation, and spin–torsion-rotation. All three tests produced a lower RMS. westerfit paves a way forward for complete treatment of spin–torsion–rotation problems regardless of barrier height or quadrupole moment.
期刊介绍:
The Journal of Molecular Spectroscopy presents experimental and theoretical articles on all subjects relevant to molecular spectroscopy and its modern applications. An international medium for the publication of some of the most significant research in the field, the Journal of Molecular Spectroscopy is an invaluable resource for astrophysicists, chemists, physicists, engineers, and others involved in molecular spectroscopy research and practice.