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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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conveners, pyroelectric radiant-energy receivers, and nonlinear
capacitive elements. Most lerroelectiics are metal oxides1"' !'M (such as
BaTiO( and LiNbO,K a few are liquid-crystal materials.1 1
In a further development of the slush kebab class of polymers,
metalloporphyi'in -coordination polymers have been suggested as possible
lerroelectiic materials.Ifil>J u-~m Coordination polymers of nonplanai
metalloporphyrins with nonyyH/metrical bridging ligands carry an aligned
Figure 106. Schematic of zeolite L main channel {top) and idealized
Zn(TMPyP4 1 ) methylviologen (MV2 + )n complex {bottom). Reprinted with
permission from Persad, L.; Bard, A. J.; Canpion, A.; Fox, M. A.;
Mallouk, . E.; Webber, S. E.; White, J. M. j. Amer. Chem. Soc. 1987,
109, 7309. (c) 1987 American Chemical Society.
EI mV vs SCE
Figure 107. Cyclic voltammograms obtained for Cu(TPP)/zeolite Y modified
carbon-paste electrode in absence (A), presence (B) of 1.0 x 10~5molL~1
hydrazine and of 1.0 x 10~3molL 1 cysteine (C). Supporting electrolyte of
0.5 mol L "1 NaCIO^ at pH 7 and a scan rate of 20 mV s " \ Reprinted with
permission from Liu, C.-J.; Li, S.-G.; Pang, W. Q.; Che, . M. Chem.
Commun. 1997, 65.
dipole moment along the stacking axis (Figure 120). The dipole moment
originates from the charge separation between the bowl-shaped
porphyrinato core and the metal atom (Figure 121). The metal atom tends
to be pulled out of the porphyrin plane by strong axial ligands. If the
metalloporphyrin has two different axial ligands, the metal atom will be
pulled toward one side, depending on relative ligation strength and
steric demands. Various monomeric structures of metalloporphyrins201 "
204 suggest that a double-well potential can be present, as shown
schematically in Figure 122. By analogy to the metal oxide
Figure 108. Diffuse reflectance spectra of zeolite Y with encapsulated
Mn(TMP) showing porphyrin Soret band (top) and Mn(ll) ions (bottom).
Reprinted with permission from Nakamura, .; Tatsumi, .; Tominaga, H.
Bull. Chem. Soc. jpn. 1990, 63, 3334.
compounds,205-207 the direction of the bulk polarization in such
coordination polymers may respond to an external field.
Suslick and Chen have prepared several one-dimensional coordination
polymers of metal loporphyrins with nonsym-metric bridging ligands
(Figure 123) as candidates for molecular ferroelectric materials.
IH<uyy'2IXi Metalloporphyrin complexes of Fe(II), Fe(III) and Sn(IV) were
examined. Structures determined by single-crystal X-ray diffraction
include [Fe11 (TPP)(pyCN)],^, [Fe,n(TPP)-(pyCCbXk, and [Fe111
(TPP)(ImPhO)]^ (Figure 124). The chain alignment of the bridging ligand
is disordered in [Fe11 (TPP)(pyCN)]x, antiparallel in [Fe111 (TPP)(py-
02)], but aligned and polar in [FeUI(TPP)(ImPhO)]^.
41 / Porphyrin Materials Chemistry
Figure 109. Comparison of dioxygen and argon absorption isotherms of
Co(TMP)/zeolite Y material at 25 C. Reprinted with permission from Li, G.
Q.; Govind, R. Inorg. Chim. Acta. 1994, 21 7, IBS.
[Fe (TPP)(lmPhO)| v crystallizes in a non-centrosym-mctric space group,
Pna2t, with the normal to the metalloporphyrin ring about 20 off (he -
axis. Therefore, a net dipole moment or macroscopic polarization parallel
to the c-axis can be expected only from [Fe"'(TPP)-(lmPhO)J^. The small
size of the doming of the porphyrin in this complex, combined with the
large unit cell dimensions, suggests that the spontaneous polarization of
[Fe ln(TPP)(lmPhO)K will be much smaller than that of .20* 210 The
organic portion of the Fe |()(1-PhO) polymer does not contribute
much to the dipole moment, although it is the major component in the unit
Figure 111. EPR spectra of photoinduced H2(TPP' ) in TiMCM-41, MCM-41 and
AIMCM-41 after 30 minutes irradiation with >. >350nm at room temperature.
Reprinted with permission from Sung-Suh, H. .; Luan, Z.; Kevan, L./.
Phys. Chem. 1997, 101, 104SS (c) 1997 American Chemical Society,
l +



2 ! '
Figure 110. XRD patterns of (a) Ru[T(p-CI)PP](CO)(EtOH);
(b) a physical mixture of Ru[T(p-CI)PP|(CO)(EtOH) and APTES surfaced
modified MCM-41 in a mass ratio of 8:92; (c) 8.3 mass % APTES surface
modified Ru/M-41; and (d) MCM-41 and APTES surface modified MCM-41.
Reprinted with permission from Liu, C.-J.; Li, S.-.; Pang, W. Q.; Che,
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