Graphene is the two-dimensional building block for carbon allotropes of every other
dimensionality. We show that its electronic structure is captured in its Raman spectrum that clearly …

Q uantum ESPRESSO is an integrated suite of open-source computer codes for quantum
simulations of materials using state-of-the-art electronic-structure techniques, based on density-…

QUANTUM ESPRESSO is an integrated suite of computer codes for electronic-structure
calculations and materials modeling, based on density-functional theory, plane waves, and …

A theory for the ab initio calculation of all-electron NMR chemical shifts in insulators using
pseudopotentials is presented. It is formulated for both finite and infinitely periodic systems …

The adiabatic Born–Oppenheimer approximation (ABO) has been the standard ansatz to
describe the interaction between electrons and nuclei since the early days of quantum …

We present a scheme for the calculation of magnetic response parameters in insulators using
ultrasoft pseudopotentials. It uses the gauge-including projector augmented wave method […

We demonstrate that graphite phonon dispersions have two Kohn anomalies at the Γ− E 2 g
and K− A 1′ modes. The anomalies are revealed by two sharp kinks. By an exact analytic …

We calculate the double-resonant (DR) Raman spectrum of graphene, and determine the
lines associated to both phonon-defect processes (such as in the D line at∼ 1350 cm− 1, D′ …

We compute, from first principles, the frequency of the E 2 g, Γ phonon (Raman G band) of
graphene, as a function of the charge doping. Calculations are done using (i) the adiabatic …

We determine the stability, the geometry, the electronic, and magnetic structure of hydrogen-terminated
graphene-nanoribbon edges as a function of the hydrogen content of the …