The total electronic energy of hybrid MC-DCFT (HMC-DCFT) has the following form: 𝐸𝐸 HMC-DCFT = 𝐸𝐸 class + 𝑋𝑋𝐸𝐸 MC,XC + (1 -𝑋𝑋)𝐸𝐸 DC (1) where 𝐸𝐸 class is the classical energy from the multiconfigurational wave function, 𝐸𝐸 MC,XC is the MCSCF exchange-correlation energy, 𝐸𝐸 DC the nonclassical energy calculated from a DC functional, and 𝑋𝑋 is a parameter. Details of 𝐸𝐸 class and 𝐸𝐸 MC,XC are given in our earlier papers on MC-DCFT; here it suffices to note that 𝐸𝐸 class is the sum of the MCSCF kinetic energy, electron-nuclear attraction, and classical Coulomb interaction of the electronic charge distribution, and 𝐸𝐸 MC,XC is defined such that the sum of 𝐸𝐸 class and 𝐸𝐸 MC,XC is the original CASSCF energy evaluated by the wave function variational principle. Next, we explain 𝐸𝐸 DC .