상세정보
Export to Refworks부가기능
Quantum Mechanics Without Wave Functions: Advancing Orbital-Free Methods for Materials Research
상세 프로파일
| 자료유형 | 학위논문 |
|---|---|
| 서명/저자사항 | Quantum Mechanics Without Wave Functions: Advancing Orbital-Free Methods for Materials Research. |
| 개인저자 | Witt, William C. |
| 단체저자명 | Princeton University. Mechanical and Aerospace Engineering. |
| 발행사항 | [S.l.]: Princeton University., 2019. |
| 발행사항 | Ann Arbor: ProQuest Dissertations & Theses, 2019. |
| 형태사항 | 286 p. |
| 기본자료 저록 | Dissertations Abstracts International 81-05B. Dissertation Abstract International |
| ISBN | 9781687933027 |
| 학위논문주기 | Thesis (Ph.D.)--Princeton University, 2019. |
| 일반주기 |
Source: Dissertations Abstracts International, Volume: 81-05, Section: B.
Advisor: Carter, Emily A. |
| 이용제한사항 | This item must not be sold to any third party vendors. |
| 요약 | Improvements in our theoretical understanding of the material world, frequently aided by computer simulations, have led to innumerable scientific advances. While, in principle, it is advantageous to base these virtual experiments on the fundamental laws of quantum mechanics, naive application of this strategy would quickly overwhelm humanity's computing resources. Density functional theory (DFT) offers a way forward, enabling explicitly quantum-mechanical simulations that, in practice, retain much of the accuracy of the naive approach. Hundred-atom simulations utilizing standard DFT are now ubiquitous, and larger systems can be studied with more effort.Orbital-free DFT, the main subject of this dissertation, is uniquely suited to cases when large, or very fast, calculations are required. The orbital-free approach facilitates, to give some examples, study of complex Mg-Al alloys, many-atom defects in solids, and properties of liquid metals. In orbital-free DFT, the kinetic energy of an electron system is approximated from the electron density alone-and, for a given class of materials, the dramatic benefits of the orbital-free approach can only be realized if accurate approximations are found.This dissertation delivers new insights relevant to the nearly-century-long quest for a universally accurate kinetic energy approximation for orbital-free DFT. Such an approximation would revolutionize materials simulation, yielding co-benefits to many scientific disciplines. The dissertation work is unified by consideration of a nonnegative kinetic energy density (KED), analogous to the electron density, which integrates to the full kinetic energy. The first new results are summarized by first- and second-order response functionals for the KED based on a free-electron reference system. Using only the electron density as input, these response functionals can approximate the KED of nearly-free-electron systems with unprecedented accuracy, and the evidence provided suggests they will help expand the reach of orbital-free DFT. Another new result is an upper bound for the KED involving orbital-free ingredients |
| 일반주제명 | Applied physics. Materials science. |
| 언어 | 영어 |
| 바로가기 | 
: 이 자료의 원문은 한국교육학술정보원에서 제공합니다. |
