Analytic second derivatives in high-order many-body perturbation and coupled-cluster theories: Computational considerations and applications

Analytic evaluation of second derivative

Analytic evaluation of second derivatives using second-order many-body perturbation theory and unrestricted Hartree—Fock reference functions

✍ John F. Stanton; Jürgen Gauss; Rodney J. Bartlett 📂 Article 📅 1992 🏛 Elsevier Science 🌐 English ⚖ 352 KB

Explicit spin-orbital equations are presented for the second derivative of the second-order many-body perturbation theory energy based on unrestricted Hartree-Fock reference functions, and their implementation is briefly discussed. Results are reported for the electric polarizabilities, harmonic vib