Relaxed force constants (RFC) and vibrational root-mean-square (VRMS) deviations are used for comparative characterization of mechanical properties of canonical 2'-deoxyribonucleosides (2DRs) and 1,2-dideoxyribose molecule, their model sugar residue. It has been shown that RFC and VRMS should be preferred over traditional force constants when one needs to obtain the quantitative measure of the ...

A bacterial strain, GFAJ-1 was recently proposed to be substituting arsenic for phosphorus to sustain its growth. We have performed theoretical calculations for analyzing this controversial hypothesis by examining the addition of phosphate to ribose and glucose. Dispersion corrected Density Functional Theory (DFT) calculations in small molecules and QM/MM calculations on clusters derived from c...

The detailed analysis of a parallel vibration-rotation-tunneling (VRT) band of the isolated cyclic perdeuterated (d10) water pentamer measured near 2.4 THz (81.2 cm-1) is presented. The vibrationally averaged rotational constants correspond rigorously to those of a quasiplanar (C5h) oblate top whereas the equilibrium cyclic structure is predicted to be slightly asymmetric due to puckering of th...

From an equimolar dipeptide/xanthosine mixture in water/methanol, only the nucleoside crystallized in anhydrous form, space group P2,2,2, with a = 17.406 (5) A, 6 = 12.378 (4), c= 5.350 (2) A, Z = 4, C|0H 12O6N4, FW = 284.26, D x = 1.639 g • cm-3. The structure was deter­ mined by direct methods on the basis of 984 X-ray data and refined to an agreement index of R = 3.9%. Xanthosine occurs in t...

Extensive ab initio calculations were performed for the X̃ 2E′ and à 2E′′ states of Ag3, using a newly constructed basis set for Ag. An important goal of these calculations is to guide the analysis of the experimentally observed à 2E′′-X̃ 2E′ electronic spectrum. Vibrational frequencies of Ag3 for both the X̃ and à state are reported. Spectroscopically obtainable parameters describing the Jahn-Tel...

It is demonstrated that under common conditions a molecular solid subject to Jahn-Teller interactions supports stable Q-ball-like nontopological solitons. Such solitons represent a localized lump of excess electric charge in periodic motion accompanied by a time-dependent shape distortion of a set of adjacent molecules. The motion of the distortion can correspond to a true rotation or to a pseu...