Install bagel by entering the following commands in the terminal:
sudo apt update sudo apt install bagel
Computational Chemistry Package
BAGEL (Brilliantly Advanced General Electronic-structure Library) is a computational chemistry package aimed at large-scale parallel computations. It specializes on highgly accurate methods and includes density-fitting and relativistic effects for most of the methods it implements. . It can compute energies and gradients for the following methods: * Hartree-Fock (HF) * Density-Functional Theory (DFT) * Second-order Moeller-Plesset perturbation theory (MP2) * Complete active space SCF (CASSCF) * Complete active space second order perturbation theory (CASPT2) * Extended multistate CASPT2 (XMS-CASPT2) . Additionally, it can compute energies for the following methods: * Configuration-interaction singles (CIS) * Full configuration-interaction (FCI) * Multi-state internally contracted multireference configuration-interaction (ic-MRCI) * N-electron valence-state second order perturbation theory (NEVPT2) * Active-space decomposition (ASD) for dimers and for multiple sites via density matrix renormalization group (ASD-DMRG) . BAGEL is able to optimize stationary geometries and conical intersections and to compute vibrational frequencies. . BAGEL does not include a disk interface, so computations need to fit in memory.