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The u
se of b
lend
s in which a me
sogen induce
s me
somorphi
sm into a non-me
sogenic compound ha
smade po
ssib
le the
se
lf-organization of phtha
locyanine-[60]fu
llerene (Pc-C
60) dyad
s into
liquid cry
sta
ls.Pc-C
60 dyad
s 1,
2, or
3, in which two photoactive unit
s are brought together by a pheny
leneviny
lene
spacer, have been
synthe
sized through a Heck reaction that
link
s 4-viny
lbenza
ldehyde to a monoiodophtha
locyanine precur
sor, fo
llowed by
standard cyc
loaddition of azomethine y
lide
s-generated from theformy
lPc derivative and
N-methy
lg
lycine-to one of the doub
le bond
s of C
60. The me
somorphic andtherma
l propertie
s of different mixture
s formed by the
liquid-cry
sta
lline phtha
locyanine
4 and dyad
s 1,
2, or
3 were examined u
sing po
larizing optica
l micro
scopy (POM), differentia
l scanning ca
lorimetry(DSC), and X-ray diffraction (XRD). DSC diagram
s of the b
lend
s show c
lear tran
sition
s from the cry
sta
lline
state to a me
sopha
se, and the mea
sured
structura
l parameter
s obtained from the powder diffractionexperiment
s are con
si
stent with a di
scotic hexagona
l co
lumnar (Co
lh)
structure. Con
sidering that
segregationin domain
s of
separated mo
lecu
le
s of Pc-C
60 dyad and phtha
locyanine
4 wou
ld prec
lude me
somorphi
smdue to the mi
smatch in the co
lumn diameter and to the
lack of me
sogenic character of the pure dyad
s,a predominance of a
lternating
stacking i
s propo
sed. Additiona
lly, the ob
served decrea
se in the ca
lcu
latedden
sity of the b
lend me
sopha
se
s re
lative to the me
sopha
se of pure compound
4 i
s important evidence inthi
s direction.