Alkali Metal Doped Organic Molecules on Insulators: Charge Impact on the Optical Properties

Dienel, Thomas; Krause, A.; Alle, Ronald; Forker, Roman; Meerholz, Klaus; Fritz, Torsten

doi:10.1002/adma.201000891

Cited by 16 publications

(31 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…discussion section); this observation indicates that there are no appreciable interactions among the molecular transition dipoles. 32,36 At higher coverages, the formation of PTCDA molecular stacks (or at least piles) is expected. The interactions among molecular 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 9 transition dipoles in such stacks changes the spectral shape noticeably, and the bulk spectrum of PTCDA emerges.…”

Section: Resultsmentioning

confidence: 99%

“…where ܴሺ‫,ܧ‬ ݀ሻ denotes in our case the reflectivity of the sample stack consisting of the quartz 1 MLE of PTCDA partially potassium-doped providing pronounced new features of PTCDA radical anions at low photon energies (investigated in detail previously 32 ), polycrystalline (pc) PTCDA 33 and the dramatically broadened spectra of 1 MLE of PTCDA on Au(111) and Ag(111) 34,35 are shown in the bottom panel. b) Δ‫ܴܵܦ‬ of PTCDA on quartz glass for nominal thicknesses ranging from submonolayers up to 1 MLE.…”

Section: Resultsmentioning

confidence: 99%

“…This is in contrast to PTCDA adsorbed on mica where intentional doping with K is required to produce the PTCDA anion. 32 In order to investigate the origin of the PTCDA radical anion in more detail, we plot the ∆DRS spectra obtained by subtracting pairs of reflectance spectra ܴ and ܴ ାଵ representing two sequential coverages:…”

Section: Resultsmentioning

confidence: 99%

“…This situation is similar to the K-doping of PTCDA on mica, 32 where the K-doping of a monolayer of neutral PTCDA initially follows the reaction K + PTCDA → K + + PTCDA •-.…”

mentioning

confidence: 86%

“…32 There, discharging of dissolved PTCDA anions causes the low-energy spectral features (property of the PTCDA anions) to decrease while the high-energy absorbance (property of the neutral PTCDA) simultaneously increased. We decompose therefore the spectra in terms of their relative molecular oscillator strengths:…”

Section: Acs Paragon Plus Environmentmentioning

confidence: 99%

See 4 more Smart Citations

Integer Charge Transfer and Hybridization at an Organic Semiconductor/Conductive Oxide Interface

et al. 2015

Self Cite

View full text Add to dashboard Cite

We investigate the prototypical hybrid interface formed between PTCDA and conductive ndoped ZnO films by means of complementary optical and electronic spectroscopic techniques.We demonstrate that shallow donors in the vicinity of the ZnO surface cause an integer charge transfer to PTCDA, which is clearly restricted to the first monolayer. By means of DFT calculations, we show that the experimental signatures of the anionic PTCDA species can be understood in terms of strong hybridization with localized states (the shallow donors) in the substrate and charge back-donation, resulting in an effectively integer charge transfer across the interface. Charge transfer is thus not merely a question of locating the Fermi level above the PTCDA electron-transport level, but requires rather an atomistic understanding of the interfacial interactions. The study reveals that defect sites and dopants can have a significant influence on the specifics of interfacial coupling and thus on carrier injection or extraction.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

“…This situation is similar to the K-doping of PTCDA on mica, 32 where the K-doping of a monolayer of neutral PTCDA initially follows the reaction K + PTCDA → K + + PTCDA •-.…”

mentioning

confidence: 86%

Section: Acs Paragon Plus Environmentmentioning

confidence: 99%

See 3 more Smart Citations

Integer Charge Transfer and Hybridization at an Organic Semiconductor/Conductive Oxide Interface

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

Recent Progress in the Consistent Interpretation of Complementary Spectroscopic Results Obtained on Molecular Systems

Forker

Gruenewald

Kirchhuebel

et al. 2021

Advanced Optical Materials

Self Cite

View full text Add to dashboard Cite

Research on organic thin films is largely driven by potential (opto‐)electronic applications and turns out to be no less intriguing from a fundamental point of view. Numerous studies make it clear that the understanding of device‐relevant molecular thin film architectures is quite challenging—often hampered by insufficient spectroscopic data and the lack of a consistent interpretation of the available datasets. Consequently, speculative aspects prevail in the discussion of energy levels in conjunction with the optical properties of organic thin films. Adequate spectroscopic techniques applicable to thin films of organic molecules (typical thicknesses required for devices are in the nanometer range) with the necessary sensitivities are rather demanding. Some of those methods were developed or significantly improved in the recent past. Here, the now available complementary spectroscopies are briefly surveyed with particular emphasis on some techniques that have not yet become widespread standards, and a non‐exhaustive set of examples of acquired experimental results are provided. For a consistent interpretation of the latter, the concepts brought forward in the literature considering the role of initial and final states of spectroscopic processes are outlined, with important consequences for quantitatively correct energy diagrams.

show abstract

Highly ordered growth of PTCDA on epitaxial bilayer graphene

et al. 2012

View full text Add to dashboard Cite

Alkali Metal Doped Organic Molecules on Insulators: Charge Impact on the Optical Properties

Cited by 16 publications

References 46 publications

Integer Charge Transfer and Hybridization at an Organic Semiconductor/Conductive Oxide Interface

Integer Charge Transfer and Hybridization at an Organic Semiconductor/Conductive Oxide Interface

Recent Progress in the Consistent Interpretation of Complementary Spectroscopic Results Obtained on Molecular Systems

Highly ordered growth of PTCDA on epitaxial bilayer graphene

Contact Info

Product

Resources

About