Codes

PWscf can currently perform the following kinds of calculations:

• ground-state energy and one-electron (Kohn-Sham) orbitals
• atomic forces, stresses, and structural optimization
• molecular dynamics on the ground-state Born-Oppenheimer surface, also with variable-cell
• Nudged Elastic Band (NEB) and Fourier String Method Dynamics (SMD) for energy barriers and reaction paths
• phonon frequencies and eigenvectors at a generic wave vector, using Density-Functional Perturbation Theory
• effective charges and dielectric tensors
• electron-phonon interaction coefficients for metals
• interatomic force constants in real space
• third-order anharmonic phonon lifetimes
• Infrared and Raman (nonresonant) cross section
• macroscopic polarization via Berry Phase

All of the above work for both insulators and metals, in any crystal structure, for many exchange-correlation functionals (including spin polarization and LDA+U), for both norm-conserving (Hamann-Schlüter-Chiang) pseudopotentials in separable form, and -- with very few exceptions -- for Ultrasoft (Vanderbilt) pseudopotentials. Non-colinear magnetism and spin-orbit interactions are also implemented. Finite electric fields are implemented in both the supercell and the ``modern theory of polarization'' approaches (the latter is still at an experimental stage). Various postprocessing and data analysis programs are available.

CP can currently perform the following kinds of calculations:

• Car-Parrinello molecular dynamics simulation
• geometry optimization by damped dynamics
• constant-temperature simulation with Nosè thermostats (including
  Nosè-Hoover chains for each atom)
• variable-cell (Parrinello-Rahman) dynamics
• Nudged Elastic Band (NEB) for energy barriers and reaction paths
• String Method Dynamics (in real space)
• dynamics with Wannier functions and under finite electric fields

Spin-polarized calculations. CP works with both norm-conserving and Ultrasoft pseudopotentials. There are implementations of a dynamics for metals using conjugate-gradient algorithms, and of the meta-GGA functionals. Both are at an experimental stage.