Electronic Structures of Dyes and Phthalocyanines Estimated with “Photo-Electron Spectroscopy in Air (PESA)”

The near-edge electronic structures of several dyes and phtalocyanines were investigated using Photo-Electron Spectroscopy in Air (PESA). The ionization potentials (IPs) of N3, N719, Z907, D102, D149 and D205 were derived from observed photoemission threshold energies to be 5.88, 5.47, 5.44, 5.53, 5.44 and 5.49eV, respectively. Density of states (DOS) of Fe-, Ni-, Cu- and H2-phthalocyanines were deduced from differentiation of observed photoemission yields with incident photon energies. DOS thus obtained were well compared with calculated ones estimated with use of the DV-Xα molecular orbital calculation method.

ELECTRONIC STRUCTURE AND STABILITY OF NH4(NH3)n AND NH4(NH3)m(H2O)n

The photoionization process of NH 4( NH 3)n and NH 4( NH 3)m( H 2 O )n radicals produced by an ArF excimer laser photolysis of ammonia clusters and ammonia–water mixed clusters are examined using time-of-flight mass spectroscopy. The ionization potentials (IPs) of NH 4( NH 3)n (n=0−35) and NH 4( NH 3)m( H 2 O )n (m=0−4, n=0−3) are determined by the photoionization threshold measurements. The binding energies of NH 4( NH 3)n−1− NH 3 (n=1−6) are estimated from IPs. The results indicate that the bonding between NH 4 and NH 3 is semi-ionic. The IPs for the large ammoniated NH 4 clusters decrease with increasing n up to 35. The limiting value (n→∞) is found to be 1.33 eV, which coincides with the photoemission threshold of liquid NH 3. This feature is similar to those found recently for alkali-atom–ammonia clusters. A clear trend is found for the IPs of NH 4( NH 3)m( H 2 O )n; the clusters containing more water molecules have higher IP. This trend is ascribed to the large binding energy of [Formula: see text] comparing with that of [Formula: see text].