准确而高效地计算Hellmann-Feynman力,用于量子计算
Juntao Lai1, Yi Fan2, Qiang Fu1,2,3
1School of Future Technology, University of Science and Technology of China, Hefei 230026, China.
The Journal of chemical physics
|September 19, 2023
概括
本研究介绍了使用量子计算机上的变量量子eigensolver进行分析性原子力计算的方法. 这种精确的方法对小分子进行了验证,与量子化学模拟的传统技术相比,具有优势.
科学领域:
- 量子计算是一种量子计算.
- 计算化学的计算化学
- 量子力学就是量子力学.
背景情况:
- 原子力对于量子化学模拟至关重要,通常通过能量衍生物计算.
- 量子计算为复杂的量子化学问题提供了一种新的方法.
- 计算原子力的现有方法对于某些系统来说可能是计算密集的或不那么准确.
研究的目的:
- 在量子计算框架内开发和验证使用赫尔曼-费曼定理计算原子力的分析方法.
- 与古典方法相比,证明这种基于量子的方法的准确性和效率.
- 展示该方法在分子几何优化和初始分子动力学中的实际应用.
主要方法:
- 用赫尔曼-费曼定理进行分析力计算.
- 在量子计算平台上利用了变量量子自溶解器 (VQE) 算法.
- 与高级经典方法 (如完全配置交互 (FCI)) 相比,验证了结果.
主要成果:
- 对H2,LiH,H2O和NH3分子的原子力进行了准确的分析计算.
- 分析量子方法比有限差异方法的准确性更高,特别是在具有退化分子轨道的系统中.
- 成功地应用计算的力来优化分子几何形状,并执行初始分子动力学模拟.
结论:
- 开发的分析力计算方法准确且可用于实际量子化学模拟.
- 这种量子计算方法提供了显著的优势,特别是对于带有退化轨道的系统,而不会增加计算成本.
- 该方法为使用量子计算机在计算化学中进行更有效,更准确的模拟铺平了道路.
相关概念视频
The Quantum-Mechanical Model of an Atom
42.5K
Shortly after de Broglie published his ideas that the electron in a hydrogen atom could be better thought of as being a circular standing wave instead of a particle moving in quantized circular orbits, Erwin Schrödinger extended de Broglie’s work by deriving what is now known as the Schrödinger equation. When Schrödinger applied his equation to hydrogen-like atoms, he was able to reproduce Bohr’s expression for the energy and, thus, the Rydberg formula governing hydrogen spectra.
42.5K
Calculations of Electric Potential II
1.7K
An electric dipole is a system of two equal but opposite charges, separated by a fixed distance. This system is used to model many real-world systems, including atomic and molecular interactions. One of these systems is the water molecule, but only under certain circumstances. These circumstances are met inside a microwave oven, where electric fields with alternating directions make the water molecules change orientation. This vibration is equivalent to heat at the molecular level.
Consider a...
Consider a...
1.7K
Fermi Level Dynamics
278
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
278
Calculations of Electric Potential I
2.0K
Consider a ring of radius R with a uniform charge density λ. What will the electric potential be at point M, which is located on the axis of the ring at a distance x from the center of the ring?
The ring is divided into infinitesimal small arcs such that point M is equidistant from all the arcs. Here, the cylindrical coordinate system is used to calculate the electric potential at point M. A general element of the arc between angles θ and θ + dθ is of the...
The ring is divided into infinitesimal small arcs such that point M is equidistant from all the arcs. Here, the cylindrical coordinate system is used to calculate the electric potential at point M. A general element of the arc between angles θ and θ + dθ is of the...
2.0K
The Uncertainty Principle
23.4K
Werner Heisenberg considered the limits of how accurately one can measure properties of an electron or other microscopic particles. He determined that there is a fundamental limit to how accurately one can measure both a particle’s position and its momentum simultaneously. The more accurate the measurement of the momentum of a particle is known, the less accurate the position at that time is known and vice versa. This is what is now called the Heisenberg uncertainty principle. He...
23.4K
Estimation of the Physical Quantities
4.3K
On many occasions, physicists, other scientists, and engineers need to make estimates of a particular quantity. These are sometimes referred to as guesstimates, order-of-magnitude approximations, back-of-the-envelope calculations, or Fermi calculations. The physicist Enrico Fermi was famous for his ability to estimate various kinds of data with surprising precision. Estimating does not mean guessing a number or a formula at random. Instead, estimation means using prior experience and sound...
4.3K


