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Molecular doping is a key process to increase the density of charge carriers in organic semiconductors. Doping induced charges in polymer semiconductors result in the formation of polarons and or bipolarons due to the strong electron vibron coupling in conjugated organic materials. Identifying the nature of charge carriers in doped polymers is essential to optimize the doping process for applications. In this work, we use Raman spectroscopy to investigate the formation of charge carriers in molecularly doped poly 3 hexylthiophene 2,5 diyl P3HT for increasing dopant concentration, with the organic salt dimesityl borinium tetrakis penta fluorophenyl borate Mes2B [B C6F5 4] amp; 8722; and the Lewis acid tris pentafluorophenyl borane [B C6F5 3]. While the Raman signatures of neutral P3HT and singly charged P3HT segments polarons are known, the Raman spectra of doubly charged P3HT segments bipolarons are not yet sufficiently understood. Combining Raman spectroscopy measurements on doped P3HT thin films with first principles calculations on oligomer models, we explain the evolution of the Raman spectra from neutral P3HT to increasingly doped P3HT featuring polarons and eventually bipolarons at high doping levels. We identify and explain the origin of the spectral features related to bipolarons by tracing the Raman signature of the symmetric collective vibrations along the polymer backbone, which compared to neutral P3HT redshifts for polarons and blueshifts for bipolarons. This is explained by a planarization of the singly charged P3HT segments with polarons and rather high order in thin films, while the doubly charged segments with bipolarons are located in comparably disordered regions of the P3HT film due to the high dopant concentration. Furthermore, we identify additional Raman peaks associated with vibrations in the quinoid doubly charged segments of the polymer. Our results offer the opportunity for readily identifying the nature of charge carriers in molecularly doped P3HT while taking advantage of the simplicity, versatility, and non destructive nature of Raman spectroscopy

In this study, the kinetics of the adsorption of 2,3,5,6 tetrafluoro 7,7,8,8 tetracyanoquinodimethane F4TCNQ on the surface of Ag nanoparticles Ag NPs in chloroform has been intensively investigated, as molecular doping is known to play a crucial role in organic electronic devices. Based on the results obtained from UV visible vis near infrared NIR absorption spectroscopy, cryogenic transmission electron microscopy, scanning nanobeam electron diffraction, and electron energy loss spectroscopy, a two step interaction kinetics has been proposed for the Ag NPs and F4TCNQ molecules, which includes the first step of electron transfer from Ag NPs to F4TCNQ indicated by the ionization of F4TCNQ and the second step of the formation of a Ag F4TCNQ complex. The whole process has been followed via UV vis NIR absorption spectroscopy, which reveals distinct kinetics at two stages the instantaneous ionization and the long term complex formation. The kinetics and the influence of the molar ratio of Ag NPs F4TCNQ molecules on the interaction between Ag NPs and F4TCNQ molecules in an organic solution are reported herein for the first time. Furthermore, the control experiment with silica coated Ag NPs manifests that the charge transfer at the surface between Ag NPs and F4TCNQ molecules is prohibited by a silica layer of 18 nm

Previous research has shown that orthographic marking may have a function beyond identifying orthographic word forms. In two visual priming experiments with native speakers and advanced learners of German (Czech natives) we tested the hypothesis that orthography can convey word-class cues comparable to morphological marking. We examined the effect of initial letter capitalization of nouns (a specific property of German orthography) on the processing of five homonymous and grammatically ambiguous forms. Both populations showed the same pattern of results: deverbal nouns (conversions) patterned together with countable nouns while in a previous study (with eliminated orthographic word-class cues) they patterned together with infinitives. Together, findings suggest that orthographic cues can trigger word-class-specific lexical retrieval/access. They also suggest a lexical entry structure in which conversion nouns, infinitives, and inflected verbal forms share a category-neutral parent node and that specified subnodes are accessed only when specifying cues are available and/or necessary for processing.

This joint experimental-theoretical spectroscopy study of the fullerene derivative PC

In two visual priming experiments, we investigated the relation of form-identical word forms with different grammatical functions in L1 and L2 German. Four different grammatical types (inflected verbs, infinitives, deverbal conversion forms, and countable nouns) were used as primes and their influence on the processing of form-identical inflected verbs as targets was compared. Results revealed full priming of inflected verbs, but only partial priming for conversion forms and infinitives. No priming was observed for semantically related countable nouns suggesting that they have a separate lexical entry. The findings bring first psycholinguistic evidence for typological claims that deverbal conversion nouns and infinitives fall into the category of nonfinites. They also support accounts assuming representations with a basic lexical entry and word-category specific subentries. The same priming pattern was observed in L1 and L2 suggesting that representation and processing of the studied complex forms is not fundamentally different in the two populations.

We introduce the blueprint of the Ontogenesis Model of the L2 Lexical Representation (OM) that focuses on the development of lexical representations. The OM has three dimensions: linguistic domains (phonological, orthographic, and semantic), mappings between domains, and networks of lexical representations. The model assumes that fuzziness is a pervasive property of the L2 lexicon: most L2 lexical representations are low resolution and the ontogenetic curve of their development does not reach the optimum (i.e., the ultimate stage of their attainment with optimal encoding) in one or more dimensions. We review the findings on lexical processing and vocabulary training to show that the OM has a potential to provide an interpretation for the results that have been treated separately and to move us forward in building a comprehensive model of L2 lexical acquisition and processing.

The ability to insolubilize doped semiconducting polymer layers can help enable the fabrication of efficient multilayer solution-processed electronic and optoelectronic devices. Here, we present a promising approach to simultaneously n-dope and largely insolubilize conjugated polymer films using tetrakis[{4-(1,3-dimethyl-2,3-dihydro-1

Background CD36 isoantibodies are capable of inducing neonatal alloimmune thrombocytopenia (NAIT) and platelet refractoriness. As to now the CD36 type I deficiency has been reported in East Asian and African individuals. However, it is virtually unknown in Caucasians. The aim of this study was to display the prevalence of the CD36 deficiency within parts of the Arabian population in Germany. Secondly, we are presenting the case of a newborn suffering from NAIT which was induced by CD36 antibody. Methods Platelet (p) CD36 was determined by flow cytometry on 1328 samples mainly from individuals of Arabian origin and a family with a neonate affected by NAIT. DNA sequencing was performed on all pCD36-negative samples. Results Thirty-five (2.64%) of all donor samples were pCD36 negative, 19 (1.43%) had a weak expression. Including only individuals from the Arabian peninsula, frequencies were 3.39% and 1.75%, respectively. CD36 type I deficiency on both platelets and monocytes combined with a CD36 isoantibody were detected in the mother of the NAIT baby. The baby was successfully transfused with two HPA-unselected platelet concentrates. In case of need, two platelet units with a weak pCD36 expression were on hand. A total of 45 different CD36 mutations were detected within pCD36-negative individuals, some being homozygous, most of them only present on one allele. Conclusion The CD36-negative phenotype is present in a significant number of individuals of Arabian origin and enables CD36 isoimmunization in NAIT or refractoriness. Blood transfusion services should be aware of such cases.

In the present study we challenge the generally accepted view based primarily on L1 data that surface linguistic information decays rapidly during reading and that only propositional information is retained in memory. In two eye-tracking experiments, we show that both L1 and L2 adult readers retain verbatim information of a text. In particular, the reading behaviour of L2 German learners revealed that they were sensitive to both lexical (synonyms) and syntactic (active/passive alternation) substitutions during a second reading of the texts, while L1 exhibited only reduced sensitivity to the lexical substitutions. The results deliver an important piece of evidence that complies with several current processing (e.g., Shallow Structure Hypothesis), acquisition (Declarative/Procedural Model) and cognitive (e.g., Fuzzy Trace Theory) approaches and adds a new dimension to their empirical and theoretical basis.

The electrical and optoelectronic properties of organic semiconductor thin films can be tailored by mixing two molecular materials, e.g., by co-deposition. Possible resulting morphologies include p...

Optical absorption spectroscopy is a key method to investigate doped conjugated polymers and to characterize the doping-induced charge carriers, i.e., polarons. For prototypical poly(3-hexylthiophene-2,5-diyl) (P3HT), the absorption intensity of molecular dopant induced polarons is widely used to estimate the carrier density and the doping efficiency, i.e., the number of polarons formed per dopant molecule. However, the dependence of the polaron-related absorption features on the structure of doped P3HT, being either aggregates or separated individual chains, is not comprehensively understood in contrast to the optical absorption features of neutral P3HT. In this work, we unambiguously differentiate the optical signatures of polarons on individual P3HT chains and aggregates in solution, notably the latter exhibiting the same shape as aggregates in solid thin films. This is enabled by employing tris(pentafluorophenyl)borane (BCF) as dopant, as this dopant forms only ion pairs with P3HT and no charge transfer complexes, and BCF and its anion have no absorption in the spectral region of P3HT polarons. Polarons on individual chains exhibit absorption peaks at 1.5 eV and 0.6 eV, whereas in aggregates the high-energy peak is split into a doublet 1.3 eV and 1.65 eV, and the low-energy peak is shifted below 0.5 eV. The dependence of the fraction of solvated individual chains versus aggregates on absolute solution concentration, dopant concentration, and temperature is elucidated, and we find that aggregates predominate in solution under commonly used processing conditions. Aggregates in BCF-doped P3HT solution can be effectively removed upon simple filtering. From varying the filter pore size (down to 200 nm) and thin film morphology characterization with scanning force microscopy we reveal the aggregates' size dependence on solution absolute concentration and dopant concentration. Furthermore, X-ray photoelectron spectroscopy shows that the dopant loading in aggregates is higher than for individual P3HT chains. The results of this study help understanding the impact of solution pre-aggregation on thin film properties of molecularly doped P3HT, and highlight the importance of considering such aggregation for other doped conjugated polymers in general.

Background and Aims: Only little is known about blood groups other than ABO blood groups and Rhesus factors in Arabian countries and Iran. During the last years, increased migration to Central Europe has put a focus on the question how to guarantee blood supply for patients from these countries, particularly because hemoglobinopathies with the need of regular blood support are more frequent in patients from that region. Therefore, blood group allele frequencies should be determined in individuals from Arabian countries and Iran by molecular typing and compared to a German rare donor panel. Methods: 1,111 samples including 800 individuals from Syria, 147 from Iran, 123 from the Arabian Peninsula, and 41 from Northern African countries were included in a MALDI-TOF MS assay to detect polymorphisms coding for Kk, Fy(a/b), Fynull, Cw, Jk(a/b), Jo(a+/a–), Lu(a/b), Lu(8/14), Ss, Do(a/b), Co(a/b), In(a/b), Js(a/b), Kp(a/b), and variant alleles RHCE*c.697C>G and RHCE*c.733C>G. Yt(a/b), S–s–U–, Velnull, Conull, and RHCE*c.667G>T were tested by PCR-SSP. Results: Of the Arabian donors, 2% were homozygous for the FY*02.01N allele (Fynull), and 15.7% carried the heterozygous mutation. However, 0.8% of the German donors also carried 1 copy of the allele. 3.6% of all and 29.3% of Northern African donors were heterozygous for the RHCE*c.733C>G substitution, 0.4% of the Syrian probands were heterozygous for DO*01/DO*01.-05, a genotype that was lacking in German donors. Whereas the KEL*02.06 allele coding for the Js(a) phenotype was missing in Germans; 0.8% of the Syrian donors carried 1 copy of this allele. 1.8% of the Syrian but only 0.3% of the German donors were negative for YT*01. One donor from Northern Africa homo­zygously carried the GYPB*270+5g>tmutation, inducing the S–s–U+w phenotype, and in 2 German donors a GYPB*c.161G>A exchange, which induces the Mit+ phenotype, caused a GYPB*03 allele dropout in the MALDI assay. The overall failure rate of the Arabian panel was 0.4%. Conclusions: Some blood group alleles that are largely lacking in Europeans but had been described in African individuals are present in Arabian populations at a somewhat lower frequency. In single cases, it could be challenging to provide immunized Arabian patients with compatible blood.

Surface-defect passivation is key to achieving high photoluminescence quantum yield in lead halide perovskite nanocrystals. However, in perovskite light-emitting diodes these surface ligands also have to enable balanced charge injection into the nanocrystals to yield high efficiency and operational lifetime. In this respect, alkaline halides have been reported to passivate surface trap states and increase the overall stability of perovskite light emitters. On the one side, the incorporation of alkaline ions into the lead halide perovskite crystal structure is considered to counterbalance cation vacancies, while, on the other side, the excess halides are believed to stabilise the colloids. Here, we report an organic lithium salt, viz. LiTFSI, as a halide-free surface passivation on perovskite nanocrystals. We show that the treatment LiTFSI has multiple beneficial effects on lead halide perovskite nanocrystals and LEDs derived from them. We obtain higher photoluminescence quantum yield and longer exciton lifetime, and a radiation pattern that is more favourable for light outcoupling. The ligand-induced dipoles on the nanocrystal surface shift their energy levels toward lower hole-injection barrier. Overall, these effects add up to a four- to seven-fold boost of the external quantum efficiency in proof-of-concept LED structures, depending on the color of the used lead halide perovskite nanocrystal emitters., Comment: 42 pages

In the quest towards more durable solution-processed solar cells, the stability of the active layer materials under operation conditions is important. While lifetimes of several years have been demonstrated for encapsulated organic solar cells, it is generally known that degradation events can be accounted for by air components (O2 and/or water vapour) leaking into the cell through a non-ideal sealing. Here we present a fundamental study of intentional photo-degradation of the electron-acceptor PC60BM ([6,6]-phenyl-C61-butyric acid methyl ester) in air, with the purpose of improving the understanding of the electronic effects of fullerene photo-oxidation. We have studied spincoated thin films of PC60BM by X-ray Photoelectron Spectroscopy, Near-edge X-ray Absorption Fine Structure spectroscopy, and Fourier Transform Infrared Spectroscopy, before and after exposing them to simulated sunlight in air. The changes observed in the spectra obtained by these complementary methods were compared with calculated spectra of a large set of possible oxidation products of PC60BM where oxygen atoms have been attached to the C60 cage. The best fit with experimental IR spectra of photodegraded PC60BM films was obtained for a linear combination of calculated spectra for two degradation products, a dicarbonyl and an anhydride, both with open cages with 58 carbon atoms, and the pristine PC60BM molecule. From this comparison, we conclude that the conjugation of the fullerene cage is disturbed by the formation of several carbonyl-based derivatives on the C60 cage, accompanied by a transition from sp2 to sp3-hybridized carbon. The π* resonance in the C1s NEXAFS spectrum was found to be a very sensitive probe for small changes to the fullerene cage, and FT-IR was needed in combination with O1s NEXAFS, to identify the oxidation products. Article part of Blazinic's (2019) doctoral thesis Probing the effects of photodegradation of acceptor materials in polymer solar cells: bulk, surface, and molecular level as manuscript.

The study explores the degree to which readers can use their previous linguistic knowledge, which goes beyond the immediate evidence in the input, to create mental representations of new words and how the employment of this knowledge may reduce the fuzziness of the new representations. Using self-paced reading, initial representations of novel identical forms with different grammatical functions were compared in native German speakers and advanced L2 German learners with L1 Czech. The results reveal that although both groups can employ general knowledge about German grammar when establishing new representations, the L1 native speakers outperform the L2 learners: Their new representations have more precise structure and are better differentiated from related representations with respect to their grammatical information. Modeling consequences of these findings are discussed in the context of the Ontogenesis Model of the L2 Lexical Representation and the Fuzzy Lexical Representation Hypothesis.

Polyethylenimine (PEI) layers are used as cathode interlayer to reduce the work function of electrode materials and are frequently applied to organic or perovskite opto-electronic devices. PEI was applied from solution on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate mixture, zinc oxide and graphite. Choice of solvent and residual solvent removal ensure the superior functionality. [1] Furthermore, a single-step formation of a low work function cathode interlayer and n‑type bulk doping from semiconducting polymer/PEI blend solution was observed. [2] [1] S. Bontapalle et al., Adv. Mater. Interface 7 (2020) 2000291. [2] K. Seidel et al., ACS Appl. Mater. Interfaces 12 (2020) 28801.

Efficient electrical doping of organic semiconductors relies on identifying appropriate molecular dopants that are capable of ionizing semiconductor molecules with a high yield, thereby creating mobile charges. We explore the suitability of two different material parameters to predict ion pair formation for different sets of semiconductor–dopant combinations: (i) redox-potentials measured by cyclic voltammetry in solution and (ii) ionization energy (IE)/electron affinity (EA) measured on thin films by ultraviolet/inverse photoelectron spectroscopy. Our study suggests, at least for molecular semiconductors and dopants, that redox-potentials are better suited to identify matching material pairs and their ion pair formation yield than IE/EA values. This is ascribed to the dependence of IE/EA values on molecular orientation and film structure on and above the meso-scale. In contrast, cyclic voltammetry measurements, although performed on solutions rather than on thin films, capture dopant–semiconductor energy levels on the molecular scale, which is more relevant for doping even in the case of solid thin films.

Doping the electron transport polymer poly [N,N amp; 8242; bis 2 octyldodecyl naphthalene 1,4,5,8 bis dicarboximide 2,6 diyl] alt 5,5 amp; 8242; 2,2 amp; 8242; bithiophene [P NDI2OD T2 ] with the bulky, strongly reducing metallocene 1,2,3,4,1 amp; 8242;,2 amp; 8242;,3 amp; 8242;,4 amp; 8242; octaphenylrhodocene OPR leads to an increased bulk conductivity and a decreased contact resistance. While the former arises from low level n doping of the intrinsic polymer and increased carrier mobility due to trap filling, the latter arises from a pronounced accumulation of dopant molecules at an indium tin oxide ITO substrate. Electron transfer from OPR to ITO leads to a work function reduction, which pins the Fermi level at the P NDI2OD T2 conduction band and thus minimizes the electron injection barrier and the contact resistance. The results demonstrate that disentangling the effects of electrode modification by the dopant and bulk doping is essential to comprehensively understand doped organic semiconductors

Im vorliegenden Beitrag identifizieren wir Möglichkeiten und Grenzen einer Aufarbeitung bisher noch ungenutzter Datenquellen für raum-zeitliche Biodiversitätsanalysen in Deutschland. Im Rahmen des Syntheseprojekts sMon (https://www.idiv.de/smon) des Deutschen Zentrums für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig erprobt eine Arbeitsgemeinschaft aus Bundes- und Landesbehörden gemeinsam mit Fachgesellschaften, Verbänden und wissenschaftlichen Einrichtungen Methoden, wie heterogene Daten der letzten Jahrzehnte für retrospektive Trendanalysen genutzt werden können. Darauf aufbauend schlagen wir gangbare Wege zur Zukunft des deutschen Biodiversitätsmonitorings vor und illustrieren, wie Daten aus der Vergangenheit helfen können, Monitoring künftig zu gestalten.

Background: The federal state of Saarland (SL) is experiencing the fastest demographic change in the western part of Germany. In this study, we analyzed retrospective data on the current and future supply of red blood cell concentrates (RBC) in this region and compared it to the current and future RBC demand in SL hospitals. Methods: The projection of the SL blood supply in 2030 was modeled based on SL demographics for age distribution and donation frequency of donors, and the RBC transfusion data for in-house patients. These results were compared to published data on the transfusion demand from the state of Mecklenburg-Western Pomerania (MV). Results: For the period January 1 to December 31, 2017, a total of 43,205 whole blood donations were collected. The donation frequency in SL never exceeded 80 per 1,000 inhabitants and was well below the numbers in MV. Thirty-one percent of the donors were responsible for 53.5% of the donations, and donors older than 45 years of age contributed highly to the total blood supply. In addition, 40,614 RBC transfusions at 10 SL hospitals were analyzed representing nearly all RBC transfusions for in-house patients in this region. RBC transfusions per 1,000 inhabitants increased with age from 24 (50–54) to 140 (80–84) years. Facing an already existing structural deficit of nearly 8,200 RBC in 2017, the projection predicts a dramatic increase in the regional deficit to >18,300 RBC in 2030. Conclusion: Our results on RBC demand in SL are comparable but not identical to those projected for the region of MV in eastern Germany. Due to the ongoing demographic changes in Germany as a whole, regular regional monitoring of RBC demand and the age structure of blood recipients and donors should be implemented to allow for better strategic planning in blood transfusion services and hospitals.

Increased hole density in an electron donor-type organic semiconductor can be achieved by deposition of a strong acceptor-type molecular layer on top, and has been shown to enable adjusting the carrier density in organic field effect transistors (OFETs). This interfacial charge transfer is due to simultaneous Fermi level (EF) pinning of the donor's highest occupied level and the acceptor's lowest unoccupied level. Here, we investigate the electrical properties of such an EF-pinned junction formed by diindenoperylene (DIP, as donor) and hexafluoro-tetracyano-naphthoquinodimethane (F6, as acceptor) in OFETs, as well as its electronic properties by photoelectron spectroscopy and electrostatic modelling. We find that, in addition to the EF-pinning induced integer charge transfer across the interface, DIP and F6 form charge transfer complexes (CPXs) at their junction. The molecularly thin CPX interlayer acts as insulator and significantly reduces the density of carriers induced on either side of the junction, compared to a scenario without such an interlayer. CPX formation is thus unfavourable for the effectiveness of controlling carrier density at molecular donor/acceptor junctions by EF-pinning.

Tuning the energy levels of organic semiconductors in a predictable and durable manner is a challenging, yet necessary task to obtain high performance electronic and optoelectronic devices. Thermal diffusion and drift of dopants used for energy level control in the mostly van der Waals-cohered solids results in the degradation of the defined interfaces that all electronic and optoelectronic devices rely on. An important goal is therefore their spatial fixation in multilayer organic device stacks. This work aims at covalently functionalizing the interface of an immobilized organic semiconductor polymer. To achieve this goal, the side chains of a polyfluorene are equipped with biscyclopentadienyl moieties which undergo thermal fragmentation via retro-Diels–Alder reactions to yield cyclopentadienyl functions. Diels–Alder cycloadditions of these functional groups cross-link adjacent polymer chains. In a second step, unreacted cyclopentadienyl units at the interface are covalently functionalized with strong dienophiles through a Diels–Alder reaction from solution. This reaction sequence modifies the energetics and the work function at the interface. Transfer of our protocol to other conjugated polymers and/or reaction types paves the way to tunable energy levels at organic–organic interfaces and to universal introduction of functions at organic semiconductor interfaces after deposition from solution.

The use of polyethylenimine (PEI) as a thin interlayer between cathodes and organic semiconductors in order to reduce interfacial Ohmic losses has become an important approach in organic electronics. It has also been shown that such interlayers can form spontaneously because of vertical phase separation when spin-coating a blended solution of PEI and the semiconductor. Furthermore, bulk doping of semiconducting polymers by PEI has been claimed. However, to our knowledge, a clear delineation of interfacial from bulk effects has not been published. Here, we report a study on thin films formed by spin-coating blended solutions of PEI and poly{[N,N'-bis(2-octyldodecyl)naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} [P(NDI2OD-T2)] on indium tin oxide. We observed the vertical phase separation in such films, where PEI accumulates at the bottom and the top, sandwiching the semiconductor layer. The PEI interlayer on ITO reduces the electron injection barrier to the minimum value determined by Fermi level pinning, which, in turn, reduces the contact resistance by 5 orders of magnitude. Although we find no evidence for doping-induced polarons in P(NDI2OD-T2) upon mixing with PEI from optical absorption, more sensitive electron paramagnetic resonance measurements provide evidence for doping and an increased carrier density, at a very low level. This, in conjunction with an increased charge carrier mobility due to trap filling, results in an increase in the mixed polymer conductivity by 4 orders of magnitude relative to pure P(NDI2OD-T2). Consequently, both interfacial and bulk effects occur with notable magnitude in thin films formed from blended semiconductor polymer/PEI solution. Thus, this facile one-step procedure to form PEI interlayers must be applied with attention, as modification of the bulk semiconductor polymer (here doping) may occur simultaneously and might go un-noticed if not examined carefully.

We exploited the thermal annealing of poly(3-hexylthiophene) (P3HT) molecularly p-doped with the strong electron acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) as a tool for tuning the doping concentration as a quasi singular parameter. Via directed dopant desorption, we could unravel the complex microstructure of this semicrystalline system, leading to a detailed growth model solely based on complementary experimental evidence from scattering and spectroscopic techniques. We find the crystalline portion of p-doped P3HT to comprise regions, where dopant anions pack with the polymer chains in a metastable, cocrystalline structure with additional ionized dopants dispersed in the alkyl chain region of P3HT. Simultaneously, regions exist where the pristine polymer backbones closely pack. The dedoping via dopant desorption through thermal annealing reveals the dopants within the mixed crystalline phase to be thermally least stable. Notably, their initial desorption does not alter the th...

Current theoretical approaches to inflectional morphology make extensive use of the two concepts of abstract feature decomposition and underspecification. Psycholinguistic models of inflection, in contrast, generally lack such more differentiated morphological analyses. This paper reports a series of behavioral experiments that investigate the processing of grammatical gender of nouns in German. The results of these experiments support the idea that elements in the mental lexicon may be underspecified with regard to their grammatical features. However, contrary to all established morphological and psycholinguistic approaches, we provide evidence that even the lexical representation of bare noun stems is characterized by underspecified gender information. The observation that the domain of underspecification of grammatical features extends from inflectional markers to noun stems, supports the idea that underspecification is a more general characteristic of the mental lexicon. We conclude that this finding is mainly driven by economical reasons: a feature (or feature value) that is never used for grammatical operations (e.g., inflectional marking or evaluation of agreement) is not needed in the language system at all.

In two experiments, we explored the integration of newly learned L2 German lexical units with differing semantic properties into the L2 semantic network. Previous studies (Dagenbach et al., 1990 for L1; Bordag et al., 2016 for L2) have indicated that the access to emergent representations with weak memory traces is supported by a retrieval mechanism that inhibits their semantically related competitors with lower activation thresholds and higher selection potential. In this study used pseudowords as novel L2 items and employed semantic priming and semantic categorization tasks as well as an introspective post-test to explore whether the access to new L2 words is modulated by meaning novelty (Experiment 1) and elaborateness (Experiment 2).

In this work, two novel donor/acceptor (D/A) complexes, namely, diindenoperylene (DIP)/1,3,4,5,7,8-hexafluoro-tetracyanonaphthoquinodimethane (F6TCNNQ) and alpha-sexithiophene (6T)/F6TCNNQ, are studied. The D/A complexes segregate in form of π–π stacked D/A cocrystals and can be observed by X-ray scattering. The different conformational degrees of freedom of the donor molecules, respectively, seem to affect the thin-film crystalline texture and composition of the D/A mixtures significantly. In equimolar mixtures, for DIP/F6TCNNQ, the crystallites are mostly uniaxially oriented and homogeneous, whereas for 6T/F6TCNNQ, a mostly 3D (isotropic) orientation of the crystallites and coexistence of domains of pristine compounds and D/A complex, respectively, are observed. Using optical absorption spectroscopy, we observe for each of the two mixed systems a set of new, strong transitions located in the near-IR range below the gap of the pristine compounds: such transitions are related to charge-transfer (CT) inter...

The present study explores the early stages of incidental acquisition of grammatical gender during reading in German as a second language (L2) using a self-paced reading paradigm. The results show that advanced L2 learners are sensitive to gender agreement violations after as few as three to four exposures to a novel noun within a short text. The results also indicate that the acquisition of grammatical gender from syntactic context is gender dependent: Whereas gender violation effects were observed for feminine and neuter nouns, no such effects were observed for masculine nouns.

The Fischer indole synthesis of the ketone 1 with phenylhydrazine is studied using DFT methods. A detailed reaction mechanism is proposed and evaluated, including different plausible diaza-Cope rearrangement pathways. Cis-/trans-stereochemistry of the substrate 1 leads to different pathways and products. In addition, the influence of hydrazine protonation on the mechanism is investigated. Only implicit solvation at the PCM-M06–2X/6–311++G(d,p) level of theory predicts correctly the product stability. Furthermore, the importance of nitrogen protonation resulting in lower (and feasible) activation energies for the key step is shown. In agreement with experimental data, the pathways leading to observed products possess the lowest activation barriers. With the proposed mechanism, the correct thermodynamic and kinetic control for this rather complicated reaction is calculated, and the procedure should be able further predict regioselectivity of related systems.