# Frozen density embedding with non-integer subsystems' particle numbers.

@article{Fabiano2014FrozenDE, title={Frozen density embedding with non-integer subsystems' particle numbers.}, author={Eduardo Fabiano and Savio Laricchia and Fabio Della Sala}, journal={The Journal of chemical physics}, year={2014}, volume={140 11}, pages={ 114101 } }

We extend the frozen density embedding theory to non-integer subsystems' particles numbers. Different features of this formulation are discussed, with special concern for approximate embedding calculations. In particular, we highlight the relation between the non-integer particle-number partition scheme and the resulting embedding errors. Finally, we provide a discussion of the implications of the present theory for the derivative discontinuity issue and the calculation of chemical reactivity…

## 16 Citations

### Frozen-Density Embedding Strategy for Multilevel Simulations of Electronic Structure.

- ChemistryChemical reviews
- 2015

Modeling properties of chemical species and chemical reactions requires usually the quantum-mechanical level of description, and nonlocal embedding operators based on either transferrable pseudopotentials or frozen orbitals obtained from localization procedures have been developed in many groups.

### Density embedding with constrained chemical potential

- GeologyMolecular Physics
- 2019

We formulate a chemical-potential constrained density embedding method for systems where different fragments can have either continuum or discrete electronic states. We illustrate the method with the…

### Charge transfer excitations from exact and approximate ensemble Kohn-Sham theory.

- Physics, ChemistryThe Journal of chemical physics
- 2018

It is shown that components of Kohn-Sham ensembles can be used to describe charge transfer processes and the approximate excitation energies obtained by using the exact ensemble densities in the recently formulated ensemble Hartree-exchange theory are computed.

### eQE: An open‐source density functional embedding theory code for the condensed phase

- Chemistry
- 2017

In this work, we present the main features and algorithmic details of a novel implementation of the frozen density embedding (FDE) formulation of subsystem density functional theory (DFT) that is…

### Partition density functional theory

- Chemistry
- 2015

A PDFT functional is developed to address the issues of static correlation and delocalization errors in PDFT and an approximation for the non-additive kinetic energy is introduced and shown how this quantity can be computed exactly.

### Split electrons in partition density functional theory.

- PhysicsThe Journal of chemical physics
- 2022

Partition density functional theory is a density embedding method that partitions a molecule into fragments by minimizing the sum of fragment energies subject to a local density constraint and a…

### Accurate Reference Data for the Nonadditive, Noninteracting Kinetic Energy in Covalent Bonds.

- ChemistryJournal of chemical theory and computation
- 2017

It is found that the von Weizsäcker approximation can provide accurate NAKE in stretched covalent bonds, especially in the cases of Li2 and Na2.

### Density-based partitioning methods for ground-state molecular calculations.

- PhysicsThe journal of physical chemistry. A
- 2014

This work derives a new exact condition determining the strength of the singularities of the partition potentials at the nuclei, establishes the connection between charge-transfer and electronegativity equalization between fragments, and outlines a general strategy for overcoming delocalization and static-correlation errors in density-functional calculations.

### Subsystem density-functional theory as an effective tool for modeling ground and excited states, their dynamics and many-body interactions

- PhysicsJournal of physics. Condensed matter : an Institute of Physics journal
- 2015

This topical review focuses on some recent advances in this field related to the computation of condensed phase systems, their excited states, and the evaluation of many-body interactions between the subsystems.

### Laplacian-dependent models of the kinetic energy density: Applications in subsystem density functional theory with meta-generalized gradient approximation functionals.

- Computer ScienceThe Journal of chemical physics
- 2017

A two-dimensional scan of semilocal KED models as linear functionals of the reduced gradient and of the reduction Laplacian, for atoms and weakly bound molecular systems is presented.

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