The gaseous and ionized prototype carbonyl ylide, the distonic ion +CH2-O-CH2., is found to transfer ionized methylene to 1-adamantylphosphaacetylene (1-Ad-C equivalent to P), a kinetically stabilized phosphaalkyne, thus forming the 1-adamantylphosphaacetylenium P-methylide ion, 1-Ad-C+=P-CH2., a novel phosphorus, and the first nonclassical distonic ion. The ion abstracts CH3S. from CH3SSCH3 and both B-r and C3H5. from allyl bromide, and this characteristic reactivity demonstrates its distonic character. MO calculations at the Becke3LYP/6-311G(d,p) and MCSCF [CAS(3,3)] levels confirm that 1-Ad-C+=P-CH2. bears spatially separated charge and odd spin sites. They also reveal for the ion a phosphaallylic radical structure that stabilizes the radical site, and a a-bridged structure with three-center two-electron bonds that stabilizes the charge site. This unique electronic structure characterizes 1-Ad-C+=P-CH2. as the first nonclassical distonic ion.1223277767780