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The spreading resistance technique has been used to measure the degree of resistivity compensation in NTD‐Si samples following Au diffusion under many different conditions. From the theoretical curves of Thurber and Bullis (1) these can be converted to substitutional Au concentration distributions, Cnormals . Several new effects have been found, all of which can be interpreted using the “kick‐out” mechanism, whereby Au atoms enter substitutional sites by removing an Si atom that becomes a self‐interstitial, I . The Au diffusion process is then controlled entirely by the local concentration, CI , and out‐diffusion of these self‐interstitials. Detailed analyses and numerical solutions of the diffusion equations are given, and the experimental results can all be fitted, for instance, at 845°C using an Si self‐interstitial diffusion constant DI≧3×10−7 cm2 sec−1 . The time dependence of CS is also explained. For the first time, direct evidence for the very rapid diffusion of interstitial gold, Aunormali , is presented. It is shown that Dnormali≧10−5 cm2 sec−1 and that the equilibrium concentration of Aunormali is probably greater than or equal to the equilibrium concentration of substitutional atoms, AuS . The effect of swirl defects on Au diffusion is also demonstrated and explained.

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Abstract The reaction of l,l,l-tris(diiodarsinomethyl)ethane, CH3C(CH2Asl2)3 (1), with H2O, H2S and CH3NH2 in THF gives the adamantane cage compounds CH3C(CH2ASO)3 (4), CH3C(CH2ASS)3 (5) and CH3C(CH2ASNCH3)3 (6) in high yields. The crystal structure of 5 has been determinated by X-ray diffraction. The unit cell (space group P2i/w) contains 4 isolated molecules in a cubic closest packing. The heteroadamantane 5 has an enlarged cage structure with extremely spread C-C(H2)-As bond angles of 124° at the methylene carbon atoms. Some pharmacological properties of the adamantane derivatives 4 and 5 have been studied. All compounds have been characterized by mass spectrometry and infrared, Raman and X H NMR spectroscopy.

Lithium‐bis(diphenylphosphino)amid reagiert mit CH3I zum Bis(diphenylmethylphosphin)iminium‐iodid. Das Iodid‐Anion kann durch PF6− und B(C6H5)4− ausgetauscht werden. Das isomere [(Diphenylphosphin‐N‐methyl‐amin)‐diphenyl‐methyl‐phosphonium]iodid wurde entsprechend der Literatur dargestellt. Alle Verbindungen wurden durch IR‐, Raman‐, 1H‐ und 31P—NMR‐Spektroskopie charakterisiert.