1. Organic Bioelectronics Laboratory, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
2. Materials Science and Engineering Division, National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, United States
3. Department of Physics, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy
4. National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, United States
5. Core Laboratories, KAUST, Thuwal 23955-6900, Saudi Arabia
6. Physical Sciences and Engineering Division, KAUST, Thuwal 23955-6900, Saudi Arabia
7. Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom