Hydrogenic Stretch Spectroscopy of Glycine-Water Complexes: Anharmonic Ab Initio Classical Separable Potential Calculations.

The anharmonic frequencies of O-H, C-H, and N-H stretching modes of hydrogen-bonded glycine-HO complexes are calculated using ab initio classical separable potential approximation. In this approach, ab initio molecular dynamic simulations are used to determine an effective classical potential for each of the normal modes of the system. The frequencies are calculated by solving the time-independent Schrödinger equation for each mode using time-averaged potentials.

Approximate Quantum Dynamics using Ab Initio Classical Separable Potentials: Spectroscopic Applications.

Algorithms for quantum molecular dynamics simulations that directly use ab initio methods have many potential applications. In this article, the ab initio classical separable potentials (AICSP) method is proposed as the basis for approximate algorithms of this type. The AICSP method assumes separability of the total time-dependent wave function of the nuclei and employs mean-field potentials that govern the dynamics of each degree of freedom.

I-motif nanospheres: unusual self-assembly of long cytosine strands.

The synthesis and characterization of novel DNA structures based on tetraplex cytosine (C) arrangements, known as i-motifs or i-tetraplexes, is reported. Atomic force microscopy (AFM) investigation shows that long C-strands in mild acidic conditions form compact spherically shaped nanostructures. The DNA nanospheres are characterized by a typical uniform shape and narrow height distribution.

High-resolution STM imaging of novel single G4-DNA molecules.

The molecular morphology of long G4-DNA wires made by a novel synthetic method was, for the first time, characterized by high-resolution scanning tunneling microscopy (STM). The STM images reveal a periodic structure seen as repeating "bulbs" along the molecules. These bulbs reflect the helix morphology of the wires.