Bridged macrocyclic transition metal complexes, a new type of semiconducting materials

Abstract

Bridged quasi–one-dimensional macrocyclic transition metal complexes [MacM(L)]n using phthalocyanine (Pc), tetrabenzoporphyrine (TBP), 1,2- and 2,3-naphthalocyanines (1,2-Nc; 2,3-Nc) as macrocycles (Mac) with M = e.g., Fe, Ru, Co and L = e.g., pyrazine (pyz), 1,4-diisocyanobenzene (dib), tetrazine (tz) exhibit interesting electrical properties. Regardless of the size of the bridging ligand after either chemical or electrochemical doping stable semiconducting compounds [MacM(L)Xy]n (X = e.g., I2 BF4−, ClO4−…) are formed. For the first time the complete characterization of soluble oligomers [MacM(L)]n (Mac = t-Bu4Pc, M = Ru, L = dib, me4dib) by 1H-NMR spectroscopy is reported. Some of these shish kebab complexes, e.g., [PcM(tz)]n, (M = Fe, Ru) or [MacMCN]n; (Mac = Pc, TBP; M = Co, Fe) exhibit good semiconducting properties without additional external doping. Whether or not these compounds are intrinsic semiconductors will be discussed. The synthesis of oligomeric bridged mixed valence compounds [PcM(III)LPcM(II)L]n, (M = e.g., Fe) is another target of our work. We report here on first results of these oligomers.

SYNTHESES, STRUCTURES AND PHYSICAL PROPERTIES OF CYANIDE-BRIDGED M(II)−Ni(II) BIMETALLIC COMPLEXES WITH 2-PYRIDINEETHANOL (M(II) = Fe, Co and Ni)

“…According to these results, the complexes show a weak semiconductive behavior at room temperature. The similar conductivity measurements have been reported previously; 1.10 -10 Scm -1 for PcFe(py)CN and 3.10 -12 Scm -1 for PcCo(py)CN [30], 2.596x10 -8 Ω -1 cm -1 for Mn-Ni-etim, 2.047x10 -8 Ω -1 cm -1 for Fe-Ni-etim, 1.137x10 -7 Ω -1 cm -1 for Co-Ni-etim and 1.923x10 -9 Ω -1 cm -1 for Ni-Ni-etim [31].…”

Insulated Molecular Wires

“…The “wrapped” ladder polymer LP1 prepared by Scherf and co‐workers is another example of a conjugated polymer sheathed by its substituents 171. “Shish‐kebab” polymers such as 25 represent a related class of IMWs,172 as do ligand‐sheathed metal–metal bonded polymers such as {[Rh(MeCN) 4 ](BF 4 ) 1.5 } 8 ,173 Ni 5 11+ poly(pyridylamide) chains,174 and green [Pt(NH 2 R) 4 ][PtCl 4 ] Magnus salts,175 which resemble dendronized coordination polymers 176…”

Synthesis and Characterization of Phthalocyaninatosilicon With Bridging Ligands (L) (L = Dimethylsilane, Diphenylsilane, Methylphenylsilane)

“…The UV–vis spectra appear in terms of a porphyrinic four‐orbital model with π–π * Q‐band and Soret‐like transition and additional metal‐to‐ligand charge‐transfer ( MLCT) bands. The transition (Q‐band) of phthalocyanine causes a charge transfer from the center of the complex toward the periphery and is influenced by the electronic properties of the central metal atom . The UV–vis spectrum of [PcSi(dms)] n shows a maximum peak at 692 nm and a shoulder at 671 nm in the Q‐band and a maximum peak at 367 nm in the Soret band (B).…”

“…The a 1ue * g transition (Q-band) of phthalocyanine causes a charge transfer from the center of the complex toward the periphery and is influenced by the electronic properties of the central metal atom. 15 The UV-vis spectrum of [PcSi (dms)] n shows a maximum peak at 692 nm and a shoulder at 671 nm in the Q-band and a maximum peak at 367 nm in the Soret band (B). The maximum peak in the Q-band of [PcSi(dms)] n shifts to a shorter wavelength by 71 nm for PcSiCl 2.…”