Production of highly concentrated 13C by continuous two-stage IRMPD. CBr2F2/HI, CCl2F2/HI, and CBrClF2/HI mixtures

Multiphoton Isotope-Selective Dissociation of Formic Acid Molecules under Action of a Free Electron Laser

“…A very large body of experimental and theoretical work on infrared multiphoton dissociation (MPD) has been accomplished since such reactions were first described over 20 years ago. − Of that work, a substantial proportion is concerned with isotope-specific MPD. − Isotopic enrichment in the gas phase of small molecules has been accomplished for sulfur, − oxygen, − hydrogen, − silicon 24 and multiple elements from the same compound. − The most extensive work has been done on carbon isotopes and most often with CO 2 lasers. − Carbon istotopic enrichment has been observed in single-wavelength, single-component reactants, − multiple-wavelength (usually two or more CO 2 laser lines) conditions 28-30 and in two-component, two-step processes. − …”

“…[19][20][21][22][23] The most extensive work has been done on carbon isotopes and most often with CO 2 lasers. [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] Carbon istotopic enrichment has been observed in single-wavelength, single-component reactants, [25][26][27] multiple-wavelength (usually two or more CO 2 laser lines) conditions [28][29][30] and in twocomponent, two-step processes. [31][32][33][34][35] These studies have lead to scale-up processes using two-step, two-component mixtures of carbon halides and halogen gases [36][37][38] and multiple-pass single-component reaction conditions.…”

“…[25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] Carbon istotopic enrichment has been observed in single-wavelength, single-component reactants, [25][26][27] multiple-wavelength (usually two or more CO 2 laser lines) conditions [28][29][30] and in twocomponent, two-step processes. [31][32][33][34][35] These studies have lead to scale-up processes using two-step, two-component mixtures of carbon halides and halogen gases [36][37][38] and multiple-pass single-component reaction conditions. 39 While the CO 2 laser frequencies are suitable for many MPD reactions, there are important fundamental vibrational frequencies such as the OH and CsH stretch in the 2.5-3.5 µm regions and CdO stretch in the 5.5-6.0 µm region which can be excited directly at these wavelengths.…”