490. The structure of the phosphonitrilic halides

Abstract

2423 the C,, type. 490. The Xtructure of the Phosphonitrilic Halides.

Phosphonitrilic Compounds: Part I. The Mechanism of Phosphonitrilic Chloride Polymerization Capacitance, Conductance, and Electron-Spin Resonance Studies

“…This contrasts markedly with other inorganic polymer systems such as organosiloxanes, borazoles, and silicon-nitrogen compounds, where the preferred steric arrangement of the six-or eight-membered ring thermody-namically favors these species relative to the higher polymers. Furthermore, the existence of dr-pa bonding between the phosphorus and nitrogen atoms in these compounds (30,31) implies that changes in ring or chain size and pianarity do not appreciably influence the stability of the system. Polymerization and depolymerization may be different aspects of the same thermal equilibration process.…”

Bericht: Recent Investigations on Cyclic Sulfur-Nitrogen-Halogen Compounds

“…The SN bond lengths of 1.605 and 1.593 A are practically equal (SN bond order 1.4 21 ). This is interpreted by DEWAR'S theory 22 , which has recently gained considerable support from FARADAY effect measurements performed by LABARRE 23 . The interpretation assumes three islands of delocalized SNS JT-bonds (d n-p n overlapping) arising by way of three-center two electron bonds between one N and two S atoms.…”

Cruciaromaticity in organometallic compounds

“…9,11) has confirmed Craig's (ref. 1) conclusion, that cyclic conjugated systems are of two types only, one obeying Htlckel's rules and the other the antithesis of those rules, according as the number of phase dislocations in the ring is even or odd. In 8 it is even, so 8 is indeed an antiaromatic analog of 10.…”