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RC and MPM thank the Chemistry Department of the
University of Aveiro (in the person of Dr Helena Nogueira),
where the FT-Raman and FT-IR experiments were carried
out. FB and NM acknowledge FCT—Unit I and D n8
226/94, and Project POCTI/QCA III (co-financed by the
european community fund FEDER)—for financial support.
NM is grateful to FCT for a PhD fellowship (PRAXIS
XXI/BD/18520/98).
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