Hybrid exchange density

B3LYP three-parameter hybrid exchange-correlation-density functional... 

B3LYP DFT method, Becke 3-parameter hybrid exchange with the Lee-Yang-Parr correlation functional DFT density functional theory... 

In Ref. [193] various non-hybrid and hybrid exchange-correlation potentials and suitable adiabatic local density approximations for the exchange-correlation kernel were... 

Most of the remaining error in DFT calculations comes from the assumption that the so-called exchange holes are localized, which causes them to fail to connect adiabatically between the KS independent-electron reference system and the real molecule. As a cure, the exchange functional is modified so it incorporates a degree of the HF exchange density, which leads to hybrid HF/DFT methods, also known as adiabatic connection models. These functionals constitute the current stare of the art in the field of DFT calculations. 

A more complex set of functionals utilizes the electron density and its gradient. These are called gradient-corrected methods. There are also hybrid methods that combine functionals from other methods with pieces of a Hartree-Fock calculation, usually the exchange integrals. 

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