Dihedral angles are evaluated for the phospholipid ligands of the lipid-binding proteins found in the Protein Data Base (PDB). Phospholipid structures occur with a trans C1-C2 configuration of the glycerol backbone and oppositely extended chains, in addition to the gauche C1-C2 rotamers found in membranes. Headgroup conformations are not restricted to the single bent-down configuration and gauc...

Recently, the surprising result that ab initio calculations on benzene and other planar arenes at correlated MP2, MP3, configuration interaction with singles and doubles (CISD), and coupled cluster with singles and doubles levels of theory using standard Pople's basis sets yield nonplanar minima has been reported. The planar optimized structures turn out to be transition states presenting one o...

Seafloor spreading at slow rates can be accommodated on large-offset oceanic detachment faults (ODFs), that exhume lower crustal and mantle rocks in footwall domes termed core complexes (OCCs). Footwall experience large rotation during exhumation, yet important aspects of the kinematics—particularly relative roles solid-block flexure—are not clearly understood. Using a high-resolution numerical...

The structure and vibrational frequencies of styrene and trans-b-methyl styrene in the lowest three singlet states ~S0 , S1 , and S2! have been calculated using ab initio quantum chemical methods. The frequencies are compared with experimental data obtained in the bulk and in a supersonic jet. The calculation shows that in the ground state the molecules have a broad shallow potential as a funct...

The existence and persistence of five-fold (quintuple) bonding in isomers of model RMMR molecules of quite different geometry are examined theoretically. The molecules studied are RMMR, with R = H, F, Cl, Br, CN, and CH3; M = Cr, Mo, and W. The potential energy surface of these molecules is quite complex, containing two, three, even four local minima. The structural preferences in these molecul...