Hydrogen bonding underpins the properties of a vast array of systems spanning a wide variety of scientific fields. From the elegance of base pair interactions in DNA to the symmetry of extended supramolecular assemblies, hydrogen bonds play an essential role in directing intermolecular forces. Yet fundamental aspects of the hydrogen bond continue to be vigorously debated. Here we use dynamic fo...

A superparamagnetic nanoparticle (SPN) is a nanometre-sized piece of a material that would, in bulk, be a permanent magnet. In the SPN the individual atomic spins are aligned via Pauli effects into a single giant moment that has easy orientations set by shape or magnetocrystalline anisotropy. Above a size-dependent blocking temperature Tb(V, τobs) , thermal fluctuations destroy the average mome...

Strong, short-ranged positional correlations involving counterions can induce a net attractive force between negatively charged strands of DNA and lead to the formation of ion pairs in dilute ionic solutions. However, the long range of the Coulomb interactions impedes the development of a simple local picture. We address this general problem by mapping the properties of a nonuniform system with...

Abstr&---A general valence force field for secondary chlorides has been refined which includes torsional force constants based on assignments of low frequency modes in model compounds. This force field also incorporates force constants related to observed intermolecular interactions. The good agreement between observed and calculated frequencies indicates that this force field will be useful in...

in this paper, a monotone positive solution is studied for buckling of a distributed model of multi walled carbon nanotube (mwcnt) cantilevers in the vicinity of thin and thick graphite sheets subject to intermolecular forces. in the modeling of intermolecular forces, van der waals forces are taken into account. a hybrid nano-scale continuum model based on lennard–jones potential is applied to ...

We present a graphical method for a unifying, quantitative analysis of molecular bonding-force measurements by atomic force microscopy (AFM). The method is applied to interpreting a range of phenomena commonly observed in the experimental AFM measurements of noncovalent, weak bonds between biological macromolecules. The analysis suggests an energy landscape underlying the intermolecular force a...