Structural determination, experimental

A comprehensive and critical compilation has been published relatively recently on gas-phase molecular geometries of sulfur compounds including sulfoxides and sulfones5. This book covers the literature up to about 1980 and contains virtually all structures determined experimentally, up to that date, either by electron diffraction or microwave spectroscopy. Here we shall highlight only some of the most important observations from that source5 and shall discuss recent results in more detail. 

Molecular model of cyclononyne showing bending of the bond angles associated with the triply bonded carbons. This model closely matches the structure determined experimentally. Notice how the staggering of bonds on adjacent atoms governs the overall shape of the ring. 

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