Abstract Ground-state integer charge transfer is commonly regarded as the basic mechanism of molecular electrical doping in both, conjugated polymers and oligomers. Here, we demonstrate that fundamentally different processes can occur two types organic semiconductors instead. Using complementary experimental techniques supported by theory, contrast a polythiophene, where p -doping leads to reportedly localized one quaterthiophene backbone segment, oligomer itself. Despite comparable relative...

GIDVis is a software package based on MATLAB specialized for, but not limited to, the visualization and analysis of grazing-incidence thin-film X-ray diffraction data obtained during sample rotation around surface normal. allows user to perform detector calibration, stitching, intensity corrections, standard evaluation (e.g. cuts integrations along specific reciprocal-space directions), crystal phase etc. To take full advantage measured in case rotation, pole figures can easily be calculated...

Substrate-induced phases (SIPs) are polymorphic that found in thin films of a material and different from the single crystal or "bulk" structure material. In this work, we investigate presence SIP family [1]benzothieno[3,2-b]benzothiophene (BTBT) organic semiconductors effect aging solvent vapor annealing on film structure. Through extensive X-ray structural investigations spin coated films, find with significantly to crystals same forms; has herringbone motif while display layered π–π...

Polymorphism and morphology can represent key factors tremendously limiting the bioavailability of active pharmaceutical ingredients (API), in particular, due to solubility issues. Within this work, generation a yet unknown surface-induced polymorph (SIP) model drug, 5,5-diphenylimidazolidin-2,4-dion (phenytoin), is demonstrated thin films through altering crystallization kinetics solvent type. Atomic force microscopy points toward presence large single-crystalline domains SIP, which...

The controlled assembly of the prototypical n‐type organic semiconductor N,N′‐1H,1H‐perfluorobutyl dicyanoperylenecarboxydiimide (PDIF‐CN 2 ) into ordered nanoarchitectures and multiscale analysis correlation between their structural electrical properties is reported. By making use Langmuir–Blodgett (LB) technique, monolayers PDIF‐CN arranged in upright standing molecular packing on different substrates are formed. Postdeposition thermal treatment makes it possible to trigger a...

The origins of specific polymorphic phases within thin films are still not well understood. polymorphism the molecule dioctyl-terthiophene is investigated during presence a silicon-oxide surface crystallisation process. It found that monolayer molecules forms two-dimensional crystals on surface. In case thicker crystalline islands formed, comparison three observed and thermodynamically more stable single crystal reveals distinct differences which can be related to an adaption molecular...

Crystal structure solutions from thin films are often performed by grazing-incidence X-ray diffraction (GIXD) experiments. In particular, on isotropic substrates the film crystallites grow in a fibre texture showing well defined crystallographic plane oriented parallel to substrate surface with random in-plane order of microcrystallites forming film. present work, analytical mathematical expressions derived for indexing experimental patterns, highly challenging task which hitherto mainly...

Pentacene is one of the most studied organic semiconducting materials. While many aspects film formation have already been identified in very thin films, this study provides new insight into transition from metastable thin-film phase to bulk polymorphs. This focuses on growth behavior pentacene within films as a function thickness ranging 20 300 nm. By employing various X-ray diffraction methods, combined with supporting atomic force microscopy investigations, crystalline orientation for...

Biopolymer cellulose is investigated in terms of the crystallographic order within thin films. The films were prepared by spin-coating a trimethylsilyl precursor followed an exposure to HCl vapors; two different source materials used. Careful precharacterization was performed infrared spectroscopy and atomic force microscopy. Subsequently, grazing incidence X-ray diffraction using synchrotron radiation. results showed broad peaks, indicating rather short correlation length molecular packing...

Epindolidione, a hydrogen-bonded derivative of the organic semiconductor tetracene, is an pigment which has previously been used to produce stable OFETs with relatively high hole mobilities. Despite its use as inkjet and semiconductor, crystal structure epindolidione proved elusive currently unknown. In this work, we report solution determined from vapor deposited thin films using combined experimental theoretical approach. The found be similar one reported derivatives most likely...

The appearance of surface-induced phases molecular crystals is a frequently observed phenomenon in organic electronics. However, despite their fundamental importance, the origin such not yet fully resolved. molecule 6,6'-dibromoindigo (Tyrian purple) forms two polymorphs within thin films. At growth temperatures 150 °C, well-known bulk structure forms, while at substrate temperature 50 phase instead. In present work, crystal polymorph solved by combined experimental and theoretical approach...

Vacuum deposition of the methoxy-functionalized p-quaterphenylene MOP4 on muscovite mica at elevated temperatures led to formation several ten micrometer long nanofibers. As shown by X-ray diffraction and polarized optical microscopy, fibers are formed lying molecules which grow epitaxially (point-on-line coincidence) along two directions a single domain. The crystal structure was induced substrate. Molecular packing calculated molecular dynamics simulations. A wetting layer from observed...

Amorphous films of the anticonvulsant drug carbamazepine are easily accessible by various methods, while crystallization into specific polymorphs represents a challenging and time-consuming task. In this work, drop cast at silica surfaces is investigated atomic force microscopy both in situ ex grazing incidence X-ray diffraction. The pristine grow with low rates triclinic polymorph, exhibiting poor orientational order within films. However, if iminostilbene, chemical precursor carbamazepine,...

An understanding of the thin film growth modes substrate-induced polymorphs allows a deeper insight into origin this class materials.

Defined fabrication of organic thin films is highly desired in technological, as well pharmaceutical, applications since morphology and crystal structure are directly linked to physical, electrical, optical properties. Within this work, the directed growth caffeine deposited by hot wall epitaxy (HWE) on muscovite mica studied. Optical atomic force microscopy measurements reveal presence needles exhibiting a preferable alignment azimuthal directions with respect orientation defined surface....

Thin films of quinacridone deposited by physical vapor deposition on silicon dioxide were investigated thermal desorption spectroscopy (TDS), mass spectrometry (MS), atomic force microscopy (AFM), specular and grazing incidence X-ray diffraction (XRD, GIXD), Raman spectroscopy. Using a stainless steel Knudsen cell did not allow the preparation pure film. TDS MS unambiguously showed that in addition to quinacridone, desorbing at about 500 K (γ-peak), significant amounts indigo desorbed 420...

By a change of texture and polymorph the dissolution characteristic drug molecule changes.

The crystallization of the nootropic drug piracetam in spin-coated thin layers on silicon oxide surfaces was analyzed by optical microscopy, as well powder and synchrotron grazing-incidence X-ray diffraction. We observed crystal structure formed to depend concentration solution used preparation samples identified either polymorphic form I (for concentrations <0.015 mol·dm–3) or II >0.147 mol·dm–3). Although significant dewetting materials occurred over time, transformation I, which is...

Defined crystal growth is highly demanded for technological applications but also fundamental research. Within this work, the of asymmetric molecule caffeine was studied on single crystalline surfaces muscovite mica, sodium chloride and potassium chloride. While elongated needle-like crystals grow mica chloride, smaller individual "bird-like" structures were observed Depending surface type temperature, disk-shaped molecules prefer either an edge-on or flat-on orientation with respect to...

A multiscale structure versus electric properties correlation of a prototypical n-type organic semiconductor assembled in different ordered nanoarchitectures, from Langmuir–Blodgett monolayer films to few monolayers-thin structures, is performed by P. Samorì and team on page 2501. The highest charge carrier mobility yet reported for LB obtained, being one order magnitude higher than the out-of-plane measured multilayered evidencing charge-transport anisotropy.