Construction of explicitly correlated one-electron reduced density matrices

Area of Science:

• Quantum Chemistry
• Computational Physics
• Materials Science

Background:

• The one-electron reduced density matrix (Γ1) is crucial for describing electronic structure.
• Conventional spectral representations of Γ1 have limitations.
• Recent work identified a discontinuity in the fifth derivative of Γ1.

Purpose of the Study:

• To develop a general construction for ensemble N-representable one-electron reduced density matrices.
• To explicitly incorporate the discontinuity in the fifth derivative of Γ1.
• To explore the relevance of this construction for density-matrix functional theory.

Main Methods:

• A novel construction of the ensemble N-representable one-electron reduced density matrix.
• Explicit inclusion of the discontinuity in the fifth derivative of Γ1.
• Analysis of the implications for density-matrix functional theory.

Main Results:

• A general construction for ensemble N-representable Γ1 is presented.
• The construction explicitly accounts for the fifth derivative discontinuity.
• The practical relevance for density-matrix functional theory is discussed.

Conclusions:

• The new construction offers a more accurate representation of the one-electron reduced density matrix.
• Incorporating the discontinuity enhances theoretical frameworks like density-matrix functional theory.
• This work advances the development of accurate electronic structure methods.