We discuss the e ects of multi-phonon excitations on heavy-ion fusion reactions at energies near and below the Coulomb barrier, focusing especially on the role of anharmonicities. We carry out a systematic study of those e ects on the excitation function of the fusion cross section and on the fusion barrier distribution, by using the vibrational limit of the interacting boson model. We also ana...

The free energy and other thermodynamic properties of hexagonal-close-packed iron are calculated by direct ab initio methods over a wide range of pressures and temperatures relevant to the Earth’s core. The ab initio calculations are based on density-functional theory in the generalisedgradient approximation, and are performed using the projector augmented wave (PAW) approach. Thermal excitatio...

The relationship between structure and properties has been followed for different nanoscale forms of tungsten disulfide (2H-WS2) namely exfoliatedmonolayer and few-layer nanoplatelets, and nanotubes. The similarities and differences between these nanostructuredmaterials have been examined using a combination of opticalmicroscopy, scanning and high-resolution transmission electronmicroscopy and ...

The free energy and other thermodynamic properties of hexagonal-close-packed iron are calculated by direct ab initio methods over a wide range of pressures and temperatures relevant to the Earth’s core. The ab initio calculations are based on density-functional theory in the generalized-gradient approximation, and are performed using the projector augmented wave approach. Thermal excitation of ...

Inelastic electron tunneling spectroscopy is a powerful technique for investigating lattice dynamics of nanoscale systems including graphene and small molecules, but establishing a stable tunnel junction is considered as a major hurdle in expanding the scope of tunneling experiments. Hexagonal boron nitride is a pivotal component in two-dimensional Van der Waals heterostructures as a high-quali...

The formation energy of a soliton was derived in the TLM model to be 2∆ 0 /π which is independent of the masses of the polymer atoms. We estimate effects of the electron-phonon coupling on the soliton formation energy, particularly, through modifications of the harmonic oscillations of (CH) groups. A model based on the amplitude mode formalism is used and the electron-phonon coupling is taken i...

The ability to probe symmetry-breaking transitions on their natural time scales is one of the key challenges in nonequilibrium physics. Stripe ordering represents an intriguing type of broken symmetry, where complex interactions result in atomic-scale lines of charge and spin density. Although phonon anomalies and periodic distortions attest the importance of electron-phonon coupling in the for...

The phonon and vtbratlonal exciton spectra are suggested as criteria for true solid solutions of molecular crystals. The short range character o f the interactions that determine both the p h o n o n and excl ton properties makes these bands ideal for distinguishing between truly random mLxed lattices and segremated microscopic domains. Raman studies o f the chemical13, mixed p-dichlorobenzene-...

Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Room temperature measurements of the far-infrared (FIR) reflectance spectra are reported for the polar optical phon...

Thermal transport in amorphous silicon dioxide (a-SiO2) is traditionally treated as random walks of vibrations owing to its greatly disordered structure, which results in a mean free path (MFP) approximately the same as the interatomic distance. However, this picture has been debated constantly and in view of the ubiquitous existence of thin a-SiO2 layers in nanoelectronic devices, it is impera...