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Development and Applications of Relativistic Correlation Consistent Basis Sets for Lanthanide Elements and Accurate Ab Initio T DEVELOPMENT AND APPLICATIONS OF RELATIVISTIC CORRELATION CONSISTENT BASIS SETS FOR LANTHANIDE ELEMENTS AND ACCURATE AB INITIO THERMOCHEMISTRY AND SPECTROSCOPY By QING LU A dissertation submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY WASHINGTON STATE UNIVERSITY Department of Chemistry MAY 2017 © Copyright by QING LU, 2017 All Rights Reserved © Copyright by QING LU, 2017 All Rights Reserved To the Faculty of Washington State University: The members of the Committee appointed to examine the dissertation of QING LU find it satisfactory and recommend that it be accepted Kirk A. Peterson, Ph.D., Chair Aurora E. Clark, Ph.D. Ursula Mazur, Ph.D. James A. Brozik, Ph.D. ii ACKNOWLEDGEMENT Having been at this step, I feel difficult to hold my emotions and think logically. So for whoever read this part, please tolerate with my ramblings. Chronologically, the first person I want to acknowledge is Prof. Ming Xian, as he offered me to the WSU grad school. Unfortunately, things didn’t work out well during my first year as I had no idea how to do research at that time. Nonetheless, I still have a good time there and I want to appreciate the help from Dr. Jia Pan and Dr. Nelmi Devarie, who were in Prof. Xian’s group and gave me lots of help. Oh, I should also thank the graduate director and search committee, whose names I forget, in the University of New Hampshire, as they gave me the first offer to cheer me up when I was applying for a US grad school back in China, and allowed me to turn down their offer after I had accepted their offer. Many thanks! Next I want to express my greatest gratefulness to my advisor, Prof. Kirk Peterson, as he gave me 2 important chances, which largely change my life. The first time is he accepted me to join his group. I still remember that after the one-year’s fail in organic chemistry, I was quite frustrated, and didn’t sleep well. I thought many times to quit the Ph.D program, but that is also a big shame to myself. Then Kirk accepted me to his lab and gave me a second chance to obtain my degree. I am really relieved at that time. The second time Kirk helps me is after my failed proposal defense. I am really grateful that he didn’t give me up, but give me another chance to take the prelim exam. I am sure this is a quite unusual thing in the department, so I can imagine there must be lots of work behind this and Kirk didn’t let me worry about it, so are my committee members, Prof. Aurora Clark, Prof. Ursula Mazur and Prof. Jim Brozik. I am very grateful for your help and patience for this confused student. Especially, I am very grateful for my committee members to fail me at my first prelim exam. iii That fail, although painful, provides me a great opportunity to think about life and universe. And after exchanging emails with Prof. Peterson during the following months, I began to know how to do research. That is my biggest harvest. Now I feel I am a totally different person from 5 years ago. A lot of things, not only in chemistry, can be seen unprecedentedly clearly. Again, I want to thank my committee members, Prof. Peterson, Prof. Brozik, Prof. Mazur and Prof. Clark for their help, care and patience. Lastly, I want to thank my family and my friends for their support during my dark time, especially my parents. They are always so supporting and patient to me, while I often release my pressure on them by shouting at them. I am so sorry for that and thank you for loving me. I wish I can be your son again in the next life I own too much to too many people. I am really sorry for my mistakes and stupidity. May Buddha and God bless you. iv DEVELOPMENT AND APPLICATIONS OF RELATIVISTIC CORRELATION CONSISTENT BASIS SETS FOR LANTHANIDE ELEMENTS AND ACCURATE AB INITIO THERMOCHEMISTRY AND SPECTROSCOPY Abstract by Qing Lu, Ph.D. Washington State University May 2017 Chair Kirk A. Peterson The relativistic correlation consistent basis sets for Lanthanide elements are developed with the 3rd-order Douglas-Kroll-Hess Hamiltonian. Atomic and molecular benchmark calculations show robust reliability of the new basis sets. Applications based on the new sets were performed, which include correcting the dissociation energy of the LuF molecule, resolving the geometry controversy of the LnX3 molecules (Ln= La, Nd, Gd, Dy, Lu; X=F, Cl, Br) and predicting the new molecules of isoelectronic to the Gd2 molecule. Spectroscopy studies of coinage metal nitroxyl molecules as well as CCX (X=P, As) radicals are also performed. The calculations should provide the most accurate theoretical results up to date. The first chapter of this dissertation briefly introduces the motivation and background of studied projects. Chapter 2 offers a summarization of the computational methods used in the study. Chapter 3 to chapter 7 present details of the studied projects. v Table of Contents Page ACKNOWLEDGEMENT ................................................................................................................................... iv ABSTRACT ... .................................................................................................................................................... vi LIST OF TABLES ............................................................................................................................................... ix LIST OF FIGURES ............................................................................................................................................. xi CHAPTER 1. INTRODUCTION ............................................................................................................................................ 1 I Background .. ..................................................................................................................................................... 1 II Summary of previous work ............................................................................................................................... 4 III Motivation and goals of current work ............................................................................................................ 10 2. REVIEW OF COMPUTATIONAL METHODS USED ................................................................................. 20 I General consideration ....................................................................................................................................... 20 II Feller-Peterson-Dixon methodology ............................................................................................................... 21 III Hartree-fock theory ........................................................................................................................................ 23 IV Correlation methods....................................................................................................................................... 25 V Relativistic hamiltonians ................................................................................................................................. 32 VI Choice of basis sets ........................................................................................................................................ 38 VII Spectroscopy calculations ............................................................................................................................ 40 3. CORRELATION CONSISTENT BASIS SETS FOR LANTHANIDES. THE ATOMS LA – LU ................ 46 I. Introduction . ................................................................................................................................................... 48 II. Basis set development .................................................................................................................................... 51 III. Results and discussion .................................................................................................................................. 56 IV. Conclusions ................................................................................................................................................... 69 vi 4. THE THERMODYNAMIC AND SPECTROSCOPIC PROPERTIES OF LNX3 (LN= LA, ND, GD, DY, LU; X=F, CL, BR) .. ................................................................................................................................................... 92 I. Introduction . ................................................................................................................................................... 92 II. Computational details ..................................................................................................................................... 96 III. Discussion . ................................................................................................................................................... 98 IV. Conclusions ................................................................................................................................................. 104 5. A COUPLED CLUSTER STUDY OF THE LUF MOLECULE WITH A REEVALUATION OF ITS BOND DISSOCIATION ENERGY .............................................................................................................................. 118 I. Introduction . ................................................................................................................................................. 118 II. Computational details ..................................................................................................................................
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