A carbon reaction studied by crossed molecular beamsa)

The chemiluminescent reaction C2+NO→CN(B 2Σ+) +CO+2.89 eV has been studied in a crossed molecular beam configuration. The carbon beam was obtained from a graphite sublimation source operating at 2550° K. The beam (principally C, C2, C3) was pulsed by a rotating slotted disk before it crossed the NO beam. Electronically excited molecules formed in reaction, CN(B 2Σ+), were detected as they rapidly decayed to the ground state. Photon time-of-arrival measurements identified the reactant as C2. The vibrational energy disposal within CN(B 2Σ+) was derived from wavelength resolved measurements. Reaction energetics and the signal intensity indicated the companion product, CO(X1Σ). This study indicates that energy deposition into vibrational degrees of CN(B 2Σ+) disagrees mildly with ’’prior expectation’’ (Levine, Bernstein, and co-workers). The reaction probably proceeds on a potential energy surface that correlates to C2(X′ 3Πu)+NO(X 2Π).