Decomposition reactions of hexafluoropropylene oxide (HFPO): Rate coefficients calculated at different temperatures using ab initio and DFT reaction paths

Molecular Insight into Real-Time Reaction Kinetics of Free Radical Polymerization from the Vapor Phase by In-Situ Mass Spectrometry

The combination of organic chemistry and chemical vapor deposition enables a unique way to deposit conformal, high quality polymer thin films from the vapor phase. Particularly initiated chemical vapor deposition (iCVD) has recently shown its great potential in many different application fields. With the ever-increasing demands on the process, the need for additional process refinement is also growing. In this study the enhancement of the iCVD process by in-situ mass spectrometry is presented. The approach enables insight into real-time reaction kinetics during the deposition process as well as identification of reaction pathways. Furthermore, the composition of the gas phase can be precisely controlled and spontaneously adjusted if necessary. Particularly the deposition of thin films with thicknesses in the low nanometer range and the deposition of copolymers can benefit from this approach. The presented approach enables enhanced process control as well as the ability to perform extensive kinetic studies.

Electron attachment to hexafluoropropylene oxide (HFPO)

We probe the electron attachment in hexafluoropropylene oxide (HFPO), C₃F₆O, a gas widely used in plasma technologies. We determine the absolute electron attachment cross section using two completely different experimental approaches: (i) a crossed-beam experiment at single collision conditions (local pressures of 5 × 10^-4 mbar) and (ii) a pulsed Townsend experiment at pressures of 20-100 mbar. In the latter method, the cross sections are unfolded from the electron attachment rate coefficients. The cross sections derived independently by the two methods are in very good agreement. We additionally discuss the dissociative electron attachment fragmentation patterns and their role in the radical production in industrial HFPO plasmas.

A theoretical study of the atmospherically important radical–radical reaction BrO + HO2; the product channel O2(a1Δg) + HOBr is formed with the highest rate

A theoretical study has been made of the BrO + HO₂ reaction, a radical–radical reaction which contributes to ozone depletion in the atmosphere via production of HOBr.