Epitaxial (001) diamond film were grown on mirror-polished single-crystalline (001) silicon substrates by microwave plasma chemical vapor deposition from a methane/hydrogen gas mixture. The films were characterized by means of scanning electron microscopy, Raman spectroscopy, and x-ray analysis. The results show that the diamond crystallites are oriented to the silicon substrate with both the (001) planes and the [110] directions parallel to the silicon substrate.

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Contrary to reports (see T. Forgan, C. Greaves, Nature 332 (1988) 14), the BiSrCaCu oxide superconductor was not first synthesized in December 1987 in Japan but rather two months earlier in Stuttgart. A patent application was submitted on November 25, 1987. X‐ray and neutron diffraction revealed that the two phases given in the title are present. The positions of the O atoms, which, on the basis of the X‐ray intensities, could only be determined with great difficulty, were found by neutron diffraction. The unique feature of the two structures is that in the (Bi2O4−δ) part they accommodate all oxidation states of Biq⊕ for 3