see cross-section of Figure 5b) are clearly visible.

Interestingly,a diluted dodecane gel of compound 2b

deposited by spin-coating on freshly cleaved HOPG leads to

self-assembly of molecular fibers that follow mainly the

preferential crystallographic directions of the underlying

HOPG substrate (Figure 5c).The threefold symmetry of

the segment pattern is particularly visible at intercepts where

the fibers form angles of 608 and 1208 to each other.The crosssections

show the presence of two types of fibers corresponding

to two different molecular heights,namely (2.0x050.1) nm

and (4.0x050.3) nm (Figure 5d).The 2-nm high fibers can be

considered to be made of single molecular layers that lie flat

on the surface (Figure S1 in the Supporting Information).The

4-nm high fibers are made of two such piled up layers,with

their alkyl chains still lying parallel to the surface.As can be

seen from the width determined by atomic force microscopy

(AFM) measurements,the fibers show a lateral extension of

several tens of nanometers.As the full lateral extension of a

single molecular wire is only about 3 nm,this result leads us to

the conclusion that the fibers are made of monolayer and

bilayer stripes that involve several molecular wires in the

lateral xy direction.

The key feature of the present molecular design is the

introduction of a flat Pt(terpy) luminophore to a 3,5-

diacylamido framework that bears gallate-substituted derivatives.

Such highly colored complexes exhibit three out-standing features:1) relative ease of synthesis and high

stability; 2) strong solvatochromism and phosphorescence

depending on the state of matter (solution or gel); and 3) the

formation of nanofibril structures or extended columnar

mesophases by switching from linear chains in 2b to branched

chains in 2c.TEM and AFM studies confirm the presence of

linear fibrils with lengths of several hundred nanometers in

dodecane gels,with their 2-nm wide core consistent with

complexes that strongly interacting through metal···metal (at

ca.3.6 G) and metal···acetylide (at ca.3.8 G) contacts.The

deep-green color and the near-infrared emission are testimony

for highly aggregated complexes and effective Pt···Pt

interactions.Additionally,amide functions are engaged in

hydrogen bonding,which accounts for additional stabilization

of the entire edifice.Fiber alignment on oriented polymer

substrates would be auspicious for charge-separation devices.

Studies along these lines are currently in progress