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If the physical properties of C(60) fullerene molecules can be controlled in C(60) products already in use in various applications, the potential for industrial development will be significant. Encapsulation of a metal atom in the C(60) fullerene molecule is a promising way to control its physical properties. However, the isolation of C(60)-based metallofullerenes has been difficult due to their insolubility. Here, we report the complete isolation and determination of the molecular and crystal structure of polar cationic Li@C(60) metallofullerene. The physical and chemical properties of Li@C(60) cation are compared with those of pristine C(60). It is found that the lithium cation is located at off-centre positions in the C(60)-I(h) cage interior and that the [Li(+)@C(60)] salt has a unique two-dimensional structure. The present method of purification and crystallization of C(60)-based metallofullerenes provides a new C(60) fullerene material that contains a metal atom.

This paper presents development of an X-ray pixel detector with a multi-port charge-coupled device (MPCCD) for X-ray Free-Electron laser experiments. The fabrication process of the CCD was selected based on the X-ray radiation hardness against the estimated annual dose of 1.6 × 10(14) photon/mm(2). The sensor device was optimized by maximizing the full well capacity as high as 5 Me- within 50 μm square pixels while keeping the single photon detection capability for X-ray photons higher than 6 keV and a readout speed of 60 frames/s. The system development also included a detector system for the MPCCD sensor. This paper summarizes the performance, calibration methods, and operation status.

By ultraclean low-pressure chemical vapor deposition (CVD) using SiH4 and GeH4 gases, low-temperature epitaxial growth of Si/Si1- x Ge x /Si heterostructures at high Ge fractions on Si(100) is achieved. The deposition rate and Ge fraction are controlled by the SiH4 and GeH4 partial pressures and the deposition temperature. Atomically flat surfaces and interfaces for the heterostructures containing Si0.8Ge0.2, Si0.5Ge0.5 and Si0.3Ge0.7 layers are obtained by deposition at 550, 500 and 450° C, respectively. Cross-sectional transmission electron microscope (TEM) images and Raman spectra show that these samples have excellent epitaxial qualities. It is also found that the Si0.5Ge0.5-channel metal-oxide-semiconductor field-effect transistor (MOSFET) has the highest peak field-effect mobility. Moreover, the atomic-layer growth of Si and Ge is achieved by the separation of surface adsorption and reaction of reactant gases. The adsorption processes of SiH4 and GeH4 are found to be described by the Langmuir adsorption-type equation.

An experimental platform for serial femtosecond crystallography using an X-ray free-electron laser and its applications at SACLA are described.