Related Experiment Video
Updated: Apr 7, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
9.8K
Density matrix embedding in an antisymmetrized geminal power bath
Takashi Tsuchimochi1, Matthew Welborn1, Troy Van Voorhis1
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139, USA.
The Journal of Chemical Physics
|July 17, 2015
Summary
Density matrix embedding theory (DMET) is enhanced with antisymmetrized geminal power (AGP) wave functions. This new AGP-DMET method accurately describes both strong and weak electron correlation in molecules.
Area of Science:
- Quantum chemistry
- Computational physics
- Materials science
Background:
- Density matrix embedding theory (DMET) is a key method for wave function-in-wave function embedding in strongly correlated systems.
- Traditional DMET uses a mean-field bath, limiting its accuracy for certain correlation regimes.
Purpose of the Study:
- To extend DMET by incorporating an antisymmetrized geminal power (AGP) wave function for the bath.
- To improve the description of electron correlation, particularly in weakly correlated and aperiodic systems.
Main Methods:
- Extension of traditional DMET equations to include AGP wave functions for the bath.
- Application of the new AGP-DMET formalism to model systems.
Main Results:
- The AGP-DMET formalism successfully treats the weak correlation limit of independent pairs.
- It provides a size-extensive correlation energy associated with a given density matrix.
- The method offers a reasonable description of charge redistribution in non-periodic, strongly correlated systems.
Conclusions:
- AGP-DMET overcomes limitations of traditional DMET by accounting for bath correlation.
- This enhanced method is well-suited for describing electron correlation in molecules, which exhibit diverse correlation types and aperiodic structures.
Related Concept Videos
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
1.9K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.9K
01:18Unit Cells
86
A crystal's internal structure is an orderly array of atoms, ions, or molecules, and the details of this array significantly influence the solid's properties. In a crystal, periodically repeating 'structural motifs' - which could be atoms, molecules, or groups thereof - create a 'space lattice.' This is essentially a three-dimensional, infinite array of points, each surrounded by its neighbors in an identical way, forming the basic structure of the crystal.A 'unit cell' is a theoretical...
86
01:12Bewley Lattice Diagram
1.6K
The Bewley lattice diagram, developed by L. V. Bewley, effectively organizes the reflections occurring during transmission-line transients. It visually represents how voltage waves propagate and reflect within a transmission line, making it easier to understand the complex interactions that occur.
1.6K
02:22Structures of Solids
21.9K
Solids in which the atoms, ions, or molecules are arranged in a definite repeating pattern are known as crystalline solids. Metals and ionic compounds typically form ordered, crystalline solids. A crystalline solid has a precise melting temperature because each atom or molecule of the same type is held in place with the same forces or energy. Amorphous solids or non-crystalline solids (or, sometimes, glasses) which lack an ordered internal structure and are randomly arranged. Substances that...
21.9K
01:24The Seven Crystal Systems: Overview
190
Crystals with various point group symmetries belong to different crystal classes, which are synonymous terms. Despite being in the same class, crystals may have distinct shapes, like cubes and octahedra. There are 32 three-dimensional point groups, all of which are systematically divided into seven crystal systems.The basic cubic crystal system, exemplified by NaCl, features orthogonal vectors (α = β = �� = 90°) of equal lengths (a = b = c). When specific...
190
02:33Lattice Centering and Coordination Number
15.8K
The structure of a crystalline solid, whether a metal or not, is best described by considering its simplest repeating unit, which is referred to as its unit cell. The unit cell consists of lattice points that represent the locations of atoms or ions. The entire structure then consists of this unit cell repeating in three dimensions. The three different types of unit cells present in the cubic lattice are illustrated in Figure 1.
Types of Unit Cells
Imagine taking a large number of identical...
Types of Unit Cells
Imagine taking a large number of identical...
15.8K