Mazzotti Fabio J, Achkasova Elena, Chauhan Richa, Tulej Marek, Radi Peter P, Maier John P
Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056, Basel, Switzerland.
Phys Chem Chem Phys. 2008 Jan 7;10(1):136-41. doi: 10.1039/b712737e. Epub 2007 Oct 25.
Four-wave mixing techniques have been used for the measurement of electronic transitions of cold transient species generated in a supersonic slit-jet discharge expansion. The origin band of the d(3)Pi(g)-a(3)Pi(u) system of C(2) and A(2)Pi(3/2)-Xcombining tildePi(3/2) electronic transition of HC(4)S were recorded. A signal-to-noise ratio of 10(4) in the spectra was achieved, resulting in detection limits of 10(10) cm(-3) for these two molecules. Application of selective two-color resonant four-wave mixing is used for the spectral assignment utilizing the double-resonance nature of the method. The combination of these techniques with a slit source proves to be a sensitive approach for the detection of transient molecules in a molecular beam discharge.
四波混频技术已被用于测量在超声速狭缝射流放电膨胀中产生的冷瞬态物种的电子跃迁。记录了C₂的d(³Πg)-a(³Πu)体系的起源带以及HC₄S的A(²Π3/2)-X̃(²Π3/2)电子跃迁。光谱中的信噪比达到了10⁴，这使得这两种分子的检测限为10¹⁰ cm⁻³。利用该方法的双共振特性，应用选择性双色共振四波混频进行光谱归属。这些技术与狭缝源的结合被证明是一种检测分子束放电中瞬态分子的灵敏方法。
