Negative parent ion in the mass spectrum of hexacarbonylvanadium

Abstract

SzmniavyThe first observation of a parent negative ion in the mass spectra of metal carbonyls is reported for v (CO) 6 .A SIGNIFICANT feature in the negative-ion mass spectra of metal carbonyls is the absence of the parent-molecule i0n.l-3This ;s consistent with the view,* based on calculations for Ni(CO),5 and Cr(C0)6,6 that the captured electron would have to be placed in an anti-bonding molecular orbital.The case of the paramagnetic hexacarbonylvanadium is dift'er jnt ; the addition of an electron to the molecule to give the anion V(C0); (which has been observed in solution) is expected since molecular orbital calculations indicate that the added electron would enter a bonding molecular orbital.'We report the observation of gaseous V(C0); formed by electron capture from V(CO),, the first observation of a parent negative ion in metal carbonyls.The complete negative ion mass spectrum of V(CO), is given in the Table . The most intense negative ion corresponds to loss of one ligand from the parent molecule; also

Low‐energy electron interactions with tungsten hexacarbonyl – W(CO)6

“…The experiment indicates that the lifetime of the W(CO) 6 –# ion is shorter than the time scales of the present experiments (> tens of µs). To our knowledge, the observation of an intact molecular anion in the mass spectra of metal carbonyls has only been reported for V(CO) 6 . In the particular case, the V(CO) 6 – anion is stable due to attachment of the extra electron to a bonding t 2g orbital .…”

“…To our knowledge, the observation of an intact molecular anion in the mass spectra of metal carbonyls has only been reported for V(CO) 6 . [17] In the particular case, the V(CO) 6 anion is stable due to attachment of the extra electron to a bonding t 2g orbital. [18] For other metal carbonyls including W(CO) 6 , the TNI is not stable, because the extra electron must occupy an anti-bonding e g orbital.…”

Dissociative electron attachment to coordination complexes of chromium: chromium(0) hexacarbonyl and benzene-chromium(0) tricarbonyl

“…Both complexes have spin-paired electrons and accordingly are diamagnetic. For such compounds, it has been postulated that DEA leads exclusively to the formation of fragment negative ions [ 26 ], without formation of parent anions, since the captured electron has to occupy an antibonding molecular orbital. In accordance with the predictions, we have observed the formation of three and seven fragment anions from Cr(CO) 6 and (η 6 -C 6 H 6 )Cr(CO) 3 , respectively, while the parent anion was not observed from any of the investigated complexes.…”