General background and highlights of CAMM research

1. General background and highlights of CAMM research The CAMM program builds upon experimental as well as theoretical approaches on the molecular level and their implications for the large-scale systems in devices for electronics and other fields. The program takes a vertical approach to studying the materials; basic research tools are developed on tractable systems and are then applied to complex materials, or systems composed of ‘hard’ electronic materials combined with polymer elements. In addition, fundamental quantum chemical calculations are used to describe trends in molecular materials properties as a function of size and composition, such as chain length of a polymer or its molecular design. These capabilities, combined with the highly sophisticated spectroscopic techniques currently in use both at MAX-lab and our home labs, have made CAMM a unique player in the field.Keywords: synchrotron radiation, new methods, new materials, theory—experiment

2. One of the long-standing challenges faced in conductivity of molecular solids is a clear understanding of the underlying mechanism for charge transport in these materials.We are investigating spintronics devices based on organic semiconductors and inorganic ferromagnetic electrodes.CAMM is a leader in the area of model molecules; here the key is a close cooperation between theoretical modeling and controlled measurements of a series of model units.Clusters are aggregates of a small number of atomic or molecular building-blocks. We have focussed on studying the development of the electronic and geometric structure from the isolated atom/molecule to the solid,One ongoing project within CAMM focuses on fundamental studies for the development of nanoporous-nanocrystalline materials for solar cells, batteries and displays. The unique capability to use tunable synchrotron radiation to follow the fate of electronic states on an ultrashort time scale was used to study charge transfer between the adsorbed molecules and the substrate.

3. Future research work • 2.1 Cluster beam synthesis of novel cluster based polymer composite materials: 2.2 MkrSvensson, Sörensen MAX investmentSvensson Upppsala Ångström • 2.2 Spintronics using molecular semiconductors 2.2 MkrSalaneck, Fahlman MAX investmentdiscussion with MAX…unknown • 2.3 Next generation nanoporous/nanocrystaline materials for energy conversion and other applications: 2.5 Mkr Siegbahn Uppsala Ångström • 2.4 Disentangling the electronic structure of molecular materials on the atomic scale 2.1 + 1.1 MkrÅgren, Sörensen KTH Biotech, MAX investment

4. Knudsen Cell and electron-ion yield detection system for MAX-Lab (BL I411 and BL I311) A very basic system containing a Knudsen Cell for controlled vaporization of molecules has been developed in Lund during Fall, 2001 and tested in early 2002. The system requires an additional investment of power supplies, pumps and diagnostic sensors for long-term use of the cell. We plan to use the cell for NEXAFS studies, and it will be used together with the electron spectrometer systems at MAX-Lab. • Knudsen Cell

5. Science • Central to CAMM are both studies of model molecules, and of molecules in the gas phase for comparison to thin film spectroscopic studies. The preliminary measurements with the Knudsen cell built by Andreas Kopp and Stacey Sörensen in 2001 have been highly successful especially given the project budget (10 kkr). Several organic molecules were measured in the vapor phase: tetracene, anthracene, naphthalene and isonicotinic acid. These measurements constitute part of collaboration with groups in Lund, Linköping, Uppsala and KTH, essentially this is a key component of collaborative CAMM projects. • The Knudsen cell system can be used as is with borrowed power supplies, and with unknown output if we do not make any further investments. We borrow from the cluster system, which will also undergo a development phase during spring 2004. It is risky to expect that all equipment will be available for two cluster sources and the Knudsen cell, so no supplementary studies of the performance of the Knudsen cell will be possible. The most severe problem is the lack of cold finger and feedback controlled heating system.

6. NEXAFS detector systems for MAX-Lab • One of the slogans of CAMM has been to implement advanced synchrotron based spectroscopic methods in both research on complex materials, and in research of industrial importance. The resonant photoemission method is again a method where the complementary strengths of CAMM members are required-theoretical development goes hand in hand with experimental measurements and new materials. • We have lost a substantial amount of time on beam line I311 where no such detection scheme is available. The lack of NEXAFS detector implies essentially a lack of photon energy calibration.Suprisingly neither of our two high-resolution beam lines at MAX have general purpose detectors for this purpose. MAX-Lab encourages this investment, but will not allow such detectors to be installed if they are not useful for all users. The original solution to cut the budget of this detector by half was rejected by Ralf Nyholm and Jesper Andersen. This investment would be beneficial for a variety of projects, cluster studies on I411, organic semiconductors on I311, core-hole clock measurements on I311 and even for Knudsen cell measurements. Note also that this instrument would make it possible to measure spectra even when the Scienta systems are not working properly.