7.1.1 August 2014
• First beamtime investigating the interaction between ice and HCOOH at PHOENIX.
• Adsorption-desorption equilibrium over a wide p(HCOOH) range, as well as a depth profile of ice exposed to 0.01 mbar HCOOH, were measured. For the depth profile analysis C1s and O1s spectra were acquired over a kinetic energy range from 2̃000-6500 eV.
• For the dosing of H2O and HCOOH high precision leak valves were used.
• The polycrystalline ice remained stable at a temperature of ~233 K over more than 24 hours.
• A pronounced carbon contamination of the ’clean’ ice before exposure to HCOOH was observed.
• Both MS were used for gas phase analysis.
7.1.2 December 2014
• Beamtime investigating the interaction between ice and HCOOH at PHOENIX.
• A depth profile of ice exposed to ~0.01 mbar HCOOH, were measured. For the depth profile analysis C1s and O1s spectra were acquired over a kinetic energy range from ~2000-4500 eV.
• For the dosing of H2O a capillary approach and for HCOOH a high precision leak valve were used.
• The polycrystalline ice remained stable at a temperature of ~233 K over about 24 hours.
• A pronounced (but slightly lower than in August 2014) carbon contamination of the ’clean’ ice before exposure to HCOOH was observed.
• Both MS were used for gas phase analysis.
7.1.3 February 2015
• Beamtime investigating the interaction between ice and HCOOH at SIM.
• During the beamtime sudden problems with the experimental set-up occurred.
Furthermore a stabilization of the ice under the beam was not possible. No valu-able analysis was possible.
• Only the MS of the differential pumping stage was used for gas phase analysis. The MS below thein-situ experimental cell was detached due to technical difficulties before the beam time. Thus the flux through the system was reduced compared to former beam times.
7.1.4 March 2015
• Beamtime investigating the interaction between ice and HCOOH at PHOENIX.
• Depth profile of ice exposed to ~0.015 mbar and 0.040 mbar HCOOH, were mea-sured. For the depth profile analysis C1s and O1s spectra were acquired over a kinetic energy range from ~2000-5500 eV.
• For the dosing of H2O and HCOOH a capillary approach was used.
• The polycrystalline ice remained relatively stable at a temperature of ~233 K over about 24 hours. However, changes in peak intensity due to evaporating ice could be observed making a detuning of the beam intensity and an increase of the H2O oversaturation necessary.
• A pronounced (peak patterns modified compared to former beamtimes) carbon contamination of the ’clean’ ice before exposure to HCOOH was observed.
• Only the MS of the differential pumping stage was used for gas phase analysis.
7.1.5 November 2015
• Beamtime investigating the interaction between ice and HCOOH at PHOENIX.
• A depth profile of ice exposed to ~0.1 mbar HCOOH, were measured. For the depth profile analysis C1s and O1s spectra were acquired over a kinetic energy range from ~2000-5500 eV.
• For the dosing of H2O and HCOOH a capillary approach was used.
• The ice consisting of few crystals remained relatively stable at a temperature of
~253 K over about 24 hours. The beam intensity was detuned.
• A pronounced carbon contamination of the ’clean’ ice before exposure to HCOOH was observed.
• Only the MS of the differential pumping stage was used for gas phase analysis.
7.1.6 December 2015
• Beamtime investigating the interaction between ice and HCOOH at SIM.
• Depth profiles of ice exposed to ~0.005 and 0.05 mbar HCOOH, were measured.
For the depth profile analysis C1s and O1s spectra were acquired over a kinetic energy range from ~150-1250 eV. Additionally C and O K-edge NEXAFS measure-ments were performed for each p(HCOOH).
• For the dosing of H2O and HCOOH a capillary approach was used.
• The ice consisting of few crystals remained relatively stable at a temperature of
~253 K over about 24 hours. The beam intensity was detuned.
• Only a negligible carbon contamination of the clean ice before exposure to HCOOH was observed.
• During the low p(HCOOH) experiments an increase of the HCOOH concentration on the ice over 100% occurred.
• Only the MS of the differential pumping stage was used for gas phase analysis.
7.1.7 February 2016
• Beamtime at SIM investigating the interaction between ice and HCOOH, HCl and MeOH, respectively.
• Depth profiles of ice exposed to ~0.01, 0.015 and 0.07 mbar HCOOH, were mea-sured. For the depth profile analysis C1s and O1s spectra were acquired over a kinetic energy range from ~150-1050 eV. Additionally C and O K-edge NEXAFS measurements were performed for each p(HCOOH).
• For HCl adsorption-desorption analysis, as well as O K-edge measurements were performed.
• C1s spectra of ice exposed to MeOH were used as a reference.
• For the dosing of H2O and HCOOH a capillary approach was used. For the dosing of HCl (in N2 carrier gas) a high precision leak valve was used.
• The ice consisting of few crystals remained relatively stable at a temperature of
~253 K over about 24 hours. The beam intensity was detuned.
• Measurements of clean ice at 233 K did not show convincing stability even though higher H2O saturations were used.
• Only a negligible carbon contamination of the clean ice before exposure was ob-served.
• Only the MS of the differential pumping stage was used for gas phase analysis.
7.1.8 April 2016
• Beamtime investigating the interaction between ice and HCl at PHOENIX.
• Depth profiles of ice exposed to HCl, as well as adsorption-desorption equilibrium were measured.
• For the dosing of H2O a capillary approach was used. For the dosing of HCl (in N2 carrier gas) a high precision leak valve was used.
• The ice consisting of few crystals and remained relatively stable at a temperature of ~253 K over about 24 hours. The beam intensity was detuned.
• Only a negligible carbon contamination of the clean ice before exposure was ob-served.
• Only the MS of the differential pumping stage was used for gas phase analysis.
7.1.9 Fall 2016
• Laboratory bases investigation of the interaction between ice and propionaldehyde at LBL.
• Adsorption-desorption equilibrium and isotherms were measured. The ice temper-ature was varied from 230-270 K.
• For the dosing of H2O and propionaldehye a high precision leak valves were used.
• The ice was crystal clear and remained stable over more than 12 hours.
• A pronounced carbon contamination of the ’clean’ ice before exposure was ob-served.
• Gas phase analysis was not possible.
7.1.10 February 2017
• Beamtime at PHOENIX investigating the interaction between ice and HCl, as well as ice and HNO3.
• Depth profiles of ice exposed to ~HCl, as well as adsorption-desorption equilibrium were measured.
• For the dosing of H2O a capillary approach was used. For the dosing of HCl and HNO3 high precision leak valves were used.
• The ice consisted of few crystals and remained relatively stable at a temperature of ~243 K over about 24 hours. The beam intensity was detuned and a pronounced H2O oversaturation needed to be used to prevent evaporation at the measurement spot.
• A pronounced carbon contamination of the clean ice before exposure was observed.
• Only the MS of the differential pumping stage was used for gas phase analysis. To increase the flow through the set-up, a further vacuum pump was attached to the system. This increases the stability of the ice tremendously.
Many people have contributed to this work. Some more direct than others. I like to thank all of them. Most probably I won’t name all of them. Not by purpose and not because I am not thankful, but I simply forgot them to mention. However, without any of you I would not have been able to finish the thesis in this way. I would therefore like to thank:
• Tom Peter for taking me on as a PhD student and for the support during this project.
• Thorsten Bartels-Rausch, for supervising my work, giving me feedback and sometimes even believing in my data when I didn’t. We had many discussions about the preparation, realization and analysis of our experiments. I am also very thankful for the many opportunities to present my work at conferences and workshops.
• Markus Ammann, for helping me with my work, giving valuable scientific input and sometimes anchoring discussions.
• Hendrik Bluhm and his group for giving me the great opportunity to come to his lab and improve my knowledge about APXPS and science in general.
• Jan Petterson for agreeing to review this work.
• Mario Birrer for fixing the things which break and building really cool new ones. He almost never was upset about broken stuff but was always happy
to help. It was a pleasure working with him. This work would not have been possible without your amazing support.
• Fabrizio Orlando, for teaching me the basics of XPS.
• Xiangrui Kong for fruitful ice discussions.
• Jacinta Edebeli and Katharina Domnanich for their time they spent reading my writings.
• All my former and current colleagues from the surface chemistry group, and the former Laboratory of Radiochemistry and Environmental Chemistry.
• I especially thank the whole NAPP team; We spent endless hours during the nights, but never got bored.
• Angela Blattmann, Doris Buehler and Petra Forney for taking care of all things bureaucratic.
• My family and friends who supported me and cared to keep me distracted.
Thanks!