Metal Carbon Bonds in Nature

Synthetic organotransition metal catalysts
(species processing a direct metal carbon or
metal hydrogen bond) are used in industrial processes to convert hydrocarbon fragments into 
industrially useful chemicals.  Transition metal alkyl species may play an important role as intermediates
in these reactions.  In contrast, biology tends to utilize CO2 or CO to form
metabolically useful compounds.  There is one biological system, referred
to as nature's organometallic catalyst namely vitamin B12 that makes use of
a MCR3 species.   B12 has cobalt .  The reaction type promoted by this
site depends on the mechanism of Co-C bond cleavage.  The accessibility
of several different oxidation states allows the versatile behavior of
this site.  Iron sulfur clusters are ubiquitous in nature and analogs
are accessible by means of synthetic methods.
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Nano Elastohydrodynamics : Structure, Dynamics and Flow in nonuniform lubricated
junctions

Structure, flow and response characteristics of molecularly thin film
of hexdecane, sheared by topographically nonuniform solid gold surfaces
sliding ata relative velocity of 10m/s are looked at with molecular dynamics
simulations.  The simulations reveal 3 characteristics : spatial and temporal
variations in the density and pressure of the lubricant in the region confined by
the approaching asperities, accompaied by asperity-induced molecular layering transitions
that are reflected in oscillatory patterns in the friction force; asperity deformations
and microstructural transformations mediated by the lubricant;
and an onset of cavitated zones in the lubricant after the
asperity-asperity collision process. The simulations extend micrometer scale elastohydrodynamic investigations
into the nanometer scale regime and provide molecular scale
insights into the fundamental mechanisms of ultrathin film lubrication
phenomena under extreme conditions.
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Nanoscale complexity of Phospholipid Monolayers investigated by Near-field
scanning optical microscopy.

Nearfield scanning optical microscopy of phospholipid
monolayers doped with fluorescent lipid analogs reveals previously undescribed
features in various phases, including concentration gradient at the liquid expanded/liquid
condensed domain boundary and weblike structures in the solid condensed phase.  Presumably,, the
web structures are grain boundaries between crystalline solid lipid.  These
structures are strongly modulated by the addition of low concentrations of 
cholesterol and ganglioside GM1 in the monolayer.