I 0.40 ( I b ) 278-280 0.63 [a] Relative to SnOz. -Shifts for SnC1& 0.50 mmisec, for SnBr6Z-0.87 mmjsec [51. 342, 330, 304, 170 i 244, 226,209 M.p. ( "C) 8 (3'P) (ppm) [bl In agreement with structure ( I ) the I R spectra contain three to four absorption bands assignable, very probably, to SnX vibrations; the presence of the H N group is shown by a band at 3130 cm-1. The molecular size could not be determined since ( l a ) and ( I b ) are insoluble in non-solvolysing media, (20) and (2b) are formed, not only by the solvolytic disproportionation of ( l a ) and ( I b ) , but also by melting ( I n ) or ( I b ) with further ((GjHs)zPO)zNH, from SnX4 and ( ( C~H S )~P O )~N N~, and by addition of Clz or Br2 to tin(1r) bis(tetrapheny1imidodiphosphinate) (5).(5) is formed on melting together tin(@ acetate and ((C6H5)2PO)NH in a vacuum. It is soluble and monomolecular in polar organic solvents and aromatic compounds, and according to its 31P-NMR spectrum it contains only equivalent phosphorus atoms, so that it is also a chelate. (2c) is obtained directly from SnI4 and ((C&S)~PO)~NH. The complexes (2) apparently exist in the cis-form; their dipole moments in dioxane amount to 7 to 8 Debyes. (2c) in CH2C12 gives two 31P-resonance signals of comparable intensity. 325-327 283-285 yellow, -28.8 -28.4 -28.0; -26.3 258-260 (dec.) (5) 215-217 --17.9 [bl Measured in CHzCIz; relative to 85 % H3P04; negative values refer to lower field strengths.Compounds (2) are cleaved back to ( I ) and ((c6H5)zPo)zNH by hydrogen halides; anhydrous perchloric acid, however, is added, yielding (4). Structure (4) is proved by equivalence of the phosphorus atoms in the 31P-NMR spectrum, the appearance of N H bands at 2925 and 2640 cm-1, and solvolytic removal of HC104 by acetonitrile or methanol, to give (6) or (2), respectively. The 1R spectra of (4) do not correspond with those of the adducts from SnX4 and ( ( C~H~)~P O ) Z N H . This confirms chemically that the correct formula for the adduct is ( I ) , and not (3).Palladium(r1) chloride crystallizes in an or-form which, according to Wells [ I ] , contains endless chains of coplanar PdC1412 units (m[PdCl4/2]; Fig. la). We have found a @-form which, according to Guinier photographs, is isotypic with the modification of platinum(~r) chloride described by Broderson, Thiele, and von Schnering[21. Thus the Pd6C112 molecules assume a space-centered arrangementk([PdsC11~]; Fig. 1 b).When tempered at 500 "C, this p-form passes into the or-form. The $-modification [Pd6C112] is formed when either form is sublimed in a vacuum. I n the mass spectrometer both modifications yield Pd6C112 molecules (mean mol. wt. 1064) with high intensity; (PdClz), molecules with n + 6 do not occur. It is therefore improbable that the Pd6C112 molecules observed have a chain or ring structure. Pd6C112 molecules (as in Fig. l b ) apparently occur in the gas phase, as in the @-modification [31. Particular interest attaches to the ready transition: chain 2 polyhedron. We attribute this to the fact that a Pd6C112 polyhedr...

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tations, while those with inorganic electron acceptors (except 0 2 ) are described as anaerobic respiration. Respiration occurs when oxygen acts as the terminal oxidant. Terms such as "fumarate respiration" and "inorganic fermentation" are incompatible with this view.A self-consistent definition of the basic metabolic types, i. e. fermentation, respiration, and photosynthesis, is provided by the relation of electron donor and acceptor systems on the one hand and the ATP* synthesizing pathways on the other (Table 1). In fermentations, ATP* is formed by substrate level phosphorylation only, whereas cell respiration is a redox process in which ATP* is synthesized mainly by electron transport phosphorylation. Photosynthesis is dominated by light-driven electron transport phosphorylations. COMMUNICATIONSInorganic fermentafion would thus be a redox process with a n inorganic electron acceptor, in which ATP* is formed exclusively by substrate level phosphorylation. Anaerobic respiration is an oxygen-free energy metabolism with an ATP* synthesis coupled to electron transport.

Die Wellenzahl der (C=S)-Valenzschwingung ist beim SCC12 verglichen mit den Wellenzahlen der anderen Thiocarbonylhalogenide verhaltnismaflig klein, was durch die zusatzliche Beteiligung einer Grenzstruktur rnit (C-S)-und (C=C1)-Bindung am Grundzustand des Thiophosgens gedeutet werden kann.Bei den schweren ubergangsmetallen kennt man Verbindungen"] mit den Gruppen [M6X8] und [M&12], x = Halogen. RegelmaRig wurde mit M = Mo oder W der erste, und mit M = Nb, Ta, Pd oder Pt der zweite Typ erhalten. Diese Regel wird jetzt zweifach durchbrochen, und zwar durch das kurzlich 121 gefundene Jodid [Nb6J&#z und das hier beschriebene Chlorid [w6c112]cl6. Wolframdichlorid [w&18]c12c14& c1 9 31 setzt sich bei cd.

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