Nanoscale amorphous marks have been produced in crystalline Ge 2 Sb 2 Te 5 films using an atomic-force microscope ͑AFM͒ and a scanning-tunneling microscope ͑STM͒ through electrical phase changes. Voltage pulses with duration of 5-100 ns applied by metal probes of the AFM and the STM can produce, respectively, high-resistance regions and deformations, the smallest sizes being ϳ10 and ϳ100 nm in diameter. Raman-scattering spectra demonstrate that these marks are amorphous. The AFM mark can be erased by applying longer pulses. Formation processes of the marks are considered from electrothermal and thermodynamic aspects.

The smallest mark which can be produced in phase-change recordings has been explored using an atomic force microscope. Electrical pulses applied to amorphous Ge 2 Sb 2 Te 5 films through conducting cantilevers can produce crystalline marks, the size decreasing with decreases in input power, pulse duration, and film thickness. The smallest mark obtained is $10 nm in diameter in a film with thickness of $1 nm. Formation mechanism of the mark is discussed.

Tetraarylanthraquinodimethane derivatives 1 with butterfly-shaped folded structures and the corresponding dications 12+ with twisted conformations can undergo interconversion upon two-electron transfer, which is accompanied by a drastic color change. While reversible electrochromic behavior occurs in solution, electron donors 1 exhibit fluorescence only in the solid state. The emission color changed upon grinding as-synthesized samples of 1, and the original emission color was recovered by a dissolving-drying process. Such mechanofluorochromic behavior can be accounted for by the results of powder X-ray diffraction (PXRD), for which as-synthesized crystalline sample was transformed into an amorphous state after grinding. Thus, the title electron donors 1 provided two-way chromic systems exhibiting electrochromism in solution as well as mechanofluorochromism in a solid state.

One-dimensional grating standards with sub-hundred nanometre pitches are required for calibration of nanometrological instruments. Nanometric lateral scales (design pitches: 100, 60 and 50 nm) for the calibration of nanometrological instruments were designed and fabricated by electron beam cell projection lithography. An offset-locked laser system consisting of an I2-stabilized He–Ne laser and a slave laser was installed in an atomic force microscope with differential laser interferometers (DLI-AFM) for the realization of a continuously, directly length-standard-traceable system and the pitches of the lateral scales were calibrated using the new DLI-AFM. The average pitches were quite close to the design pitches and the expanded uncertainties (k = 2) were less than 0.6% of the design pitches. The developed nanometric lateral scales are of sufficiently high quality and are candidates for certified reference materials (CRMs).

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