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The porphyrin handbook - Kadish K.M.

Kadish K.M. The porphyrin handbook - Academic press, 2000. - 368 p.
Download (direct link): kadishsmishgulilard2000.djvu
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T(p-Br)PP 5,10,15,20-1118(4-1)111
T(p-Cl)PP 5,10,15,20-1118(4-111)1
T(p-CN)PP 5,10,15,20-11(4-1)1
T(p-CO,H)PP 5,10,15,20-tetra(4-car boxy )111
Chou et al.
Table 1. (continued)
(DEtyP)n 5,10,15,20-Diethylnylporphyrin
T(p-F)PP 5,10,15,20-tetrakis(4-fluoropheny l)porphyrinate
T(p-NCb)PP 5,10,15,20-tetrakis(4-nitrophenyl)porphyrinate
T(p-n-OC|0H,,)PP 5,10,15,20-tetrakis(4-n-decyloxyphenol)porphyrinate
T(p-"-OCPH")PP 5,10,15,20-tetrakis(4-n-dodecyloxyphenol)porphyrinate
T(p-OCH,)PP 5,10,l5,20-tetrakis(4-methoxyphenyl)porphyrinate
T(p-OH)PP 5,10,15,20-tetra(4-hydroxyphenyl)porphyrinate
TCEMPP 5,10,15,20-tetrakis((4-
TCNE tetracyanoethylene
TFPTBP 5,10,15,20-tetrakis(3-
TFTBP 2,3,4,5-tetrakis(fluoro)tetrabenzoporphyrinate
T" glass transition temperature
THF tetrahydrofuran
THG third harmonic generation
TMAP 5,10,15,20-tetra(5-trimethylaminopenty l)porphyrinate
TMAPTBP 5,10,15,20-tetrakis(4-
TMOPTBP 5,10,15,20-tetrakis(4-
TMP 5,10,15,20-tetramethylporphyrinate
TMPTBP 5,10,15,20-tetrakis(p-
TMPyP 5,10,15,20-tetrakis(4-N-methylpyridinium)porphyrinate
TMTBP 5,10,15,20-(tetramethy l)tetrabenzoporphy ri nate
TPN 5,10,15,20-tetraphenylnaphthacene
TPP 5,10,15,20-tetraphenylporphyrinate
TPTBP 5,10,15,20-(tetraphenyl)tetrabenzoporphyrinate
TPyP 5,10,15,20-tetra-para-pyridylporphyrinate
The n-hexyl ester exhibited lower melting points than either the -butyl
or -octyl species (Table 2).6 It was noted that in both the octaether
and octaester porphyrin materials, metallation contributed a stabilizing
factor inducing wider mesomorphic temperature regimes.
The orientation of rc-nonoxyethyl octa-substituted liquid-crystalline
material was explored by X-ray diffraction. The molecules were found to
structurally order in columns such that the macrocyclic planes tilt at an
angle of 46 to the columns (Figure 2).7 The intricacy of the structure
was further elaborated for the rc-decoxyl derivative. The interfacial
porphyrin-porphyrin distance was found to be 3.98 A, and the intercolumn
separation was 23.59 A (Figure 3). This structure has been suggested as a
one-dimensional "molecular wire" motif for electronic conduction.8
Thin films of the zinc-octakis(/?-decoxyethyl)porphyrin material
included in indium-tin-oxide (ITO) electrodes were explored as an
electrooptical data storage system. Capillary filling of the porphyrin
into the ITO cell provided the physical construction of the
photoconductive system. A scanning tunneling microscope (STM) was used to
initiate charge trapping ("writing") and measurement ("reading"). A
storage density of ~ 3 gigabits per cm2 was maintained over 2000 hours of
continual subjection to charge, and greater than 60% of the current
signal was still "readable" after ~ 1500 readings. Subsequent work
demonstrated 1.5 billion "writing" and "reading" sequences of the
material without substantial change in output signal (Figure 4).9-"
Motivated by interest in exploring stronger intermole-cular
interactions than those of previously described porphyrin or
phthalocyanine mesophasic materials, Doppelt and Huille reported the
mesogenic behavior of sulfur-substituted azaporphyrin species (Figure 5).
Mesogenic phases were not observed in the free-base 2,3,7,8,12,13, 17,18-
octakis(octylthio)tetraazaporphyrin, whereas the
(/), Ni(II), Cu(II), and Zn(II) complexes revealed a discotic
hexagonal columnar liquid crystal (Dh). By optical microscopy and
differential scanning calorimetry (DSC), the cobalt material was found to
exhibit the largest mesophasic range between 48 and 206 C. The
copper(II) and the nickel(II) species manifested liquid crystalline
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