A new hypermetallic molecule LaOMn generated by laser ablation

A new hypermetallic oxide LaOMn and its positive ion involving two heterome tal atoms were observed and identified in the 532 Mm laser ablation of a La 0.67Ca0.33MnO3 target using both time-resolved quadrupole mass spectrometri c and time-of-flight mass spectrometric techniques. The dependence of LaOMn + yield on the laser fluence also confirmed the formation of the ionic hype rmetallic species. Theoretical calculations were carried out to predict the stability and the geometric structures of these new molecules. The calcula tions suggest that the LaOMn and LaOMn+ molecules might be formed via secon dary reactions of the neutral and ionic MnO with La or La+ in the laser abl ated plasma. (C) 1999 Elsevier Science B.V. All rights reserved.