A reversible, orientational switching of subphthalocyanine molecules was observed with a scanning tunneling microscope. The asymmetric, polar molecules adsorbed in an epitaxial array on a copper (100) surface, initially with its axial chlorine atom either upward or downward. After scanning at a negative bias the upward molecules turn upside down, while all molecules switched to the upward orientation at a positive bias. This flip-flop switching of the molecular array would lead to an information density of ∼60 Tbit/cm 2 .

Nucleation growth of a platinum porphyrin derivative adsorbed on a Cu (100) surface was observed with a scanning tunneling microscope. The molecule attached with four di-tert-butylphenyl groups allowed equilibrium between diffusional gas phase and two-dimensional nuclei. To minimize the free energy for nucleation, the registry of the molecules into the kink sites resulted in formation of nuclei with singular, rectangular contours. Dependence of the equilibrium conditions on the sample-tip bias voltages was also presented.Being faced with the limitation of top-down technology with semiconductors soon, a new paradigm based on molecular assembling with finite nanometer dimensions has attracted attention for high-density and high-speed devices. 1 Development of scanning tunneling microscopy (STM) 2 has realized imaging and manipulation of individual atoms and small molecules. 3-5 Molecule-based materials can ultimately be designed by assembling single molecules, the closed quantum system of which basically defines optoelectronic functions in their solid states. Structures as well as electronic properties of molecular aggregates are strongly dependent on intermolecular interactions with weak van der Waals (VDW) forces. Substrate-molecule interactions are also crucial parameters in case of constructing molecular devices in thin films. Molecular design and synthesis enable control of those interactions by modification of molecular frameworks and substitution of peripheral groups. For example, a metalloporphyrin derivative, Cu-tetra-(3,5-di-tert-butylphenyl)-porphyrin (Cu-TBPP), was the first supramolecule which attained room-temperature manipulation 6 and conformational identification 7 by STM. The four di-tert-butylphenyl (tBP) groups maintained moderate interactions with a Cu (100) surface to prevent unfavorable diffusional motion of adsorbed molecules. This molecule was further provided to demonstrate conductance switching caused by rotation of the tBP group under low-temperature STM manipulation. 8 Recently, substitution of these peripheral groups of metal-free (H 2 -) TBPP with cyanophenyl terminations dramatically modified intermolecular interactions between adjacent adsorbates on a Au (111) surface, resulting in controlled assembling from monomers to tetramers or one-dimensional (1D) wires. 9 At higher coverage of unsubstituted H 2 -TBPP on the surface, nonplanar adsorption and orientational ordering occurred in its two-dimensional (2D) islands. 10 Those reported findings suggest potential versatility of this class of supramolecules for bottom-up assembling from single molecules to higher dimensional aggregates by molecular modifications.In this study, we have synthesized TBPP substituted with a heavy central metal of platinum (Pt-TBPP, Figure 1a) according to the literature 11 and investigated dynamic processes of its 2D nucleation growth on a Cu (100) surface by low-temperature STM. The molecular structure of Pt-TBPP optimized by the ab initio molecular orbital calculation based on the density functional theory...

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On the basis of the familiarity-empathy assumption that self-disclosure evokes empathy for the speaker, it was predicted that a victim's self-disclosure would inhibit aggression against the victim. Female Japanese subjects were asked to give electric shocks to a female victim who disclosed information about herself, was not given an opportunity to do so, or rejected disclosure. Independently of self-disclosure, another empathy arousal was introduced, that is, whether or not the victim expressed her fear of shocks before they were delivered. Consistent with our hypothesis, subjects selected less severe shocks when the victim disclosed information about herself than when she was not given an opportunity to do so or when she rejected self-disclosure. The victim's expression of fear was also very effective in reducing subjects' aggression, suggesting that drawing subjects' attention to the victim's negative emotional state evoked empathy for her and reduced their aggression.