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The u
se of blend
s in which a me
sogen induce
s me
somorphi
sm into a non-me
sogenic compound ha
smade po
ssible the
self-organization of phthalocyanine-[60]fullerene (Pc-C
60) dyad
s into liquid cry
stal
s.Pc-C
60 dyad
s 1,
2, or
3, in which two photoactive unit
s are brought together by a phenylenevinylene
spacer, have been
synthe
sized through a Heck reaction that link
s 4-vinylbenzaldehyde to a monoiodophthalocyanine precur
sor, followed by
standard cycloaddition of azomethine ylide
s-generated from theformylPc derivative and
N-methylglycine-to one of the double bond
s of C
60. The me
somorphic andthermal propertie
s of different mixture
s formed by the liquid-cry
stalline phthalocyanine
4 and dyad
s 1,
2, or
3 were examined u
sing polarizing optical micro
scopy (POM), differential
scanning calorimetry(DSC), and X-ray diffraction (XRD). DSC diagram
s of the blend
s show clear tran
sition
s from the cry
stalline
state to a me
sopha
se, and the mea
sured
structural parameter
s obtained from the powder diffractionexperiment
s are con
si
stent with a di
scotic hexagonal columnar (Col
h)
structure. Con
sidering that
segregationin domain
s of
separated molecule
s of Pc-C
60 dyad and phthalocyanine
4 would preclude me
somorphi
smdue to the mi
smatch in the column diameter and to the lack of me
sogenic character of the pure dyad
s,a predominance of alternating
stacking i
s propo
sed. Additionally, the ob
served decrea
se in the calculatedden
sity of the blend me
sopha
se
s relative to the me
sopha
se of pure compound
4 i
s important evidence inthi
s direction.