An increase or modification of structural order in the vicinity a solid substrate is known for wide range materials. For molecular materials crystallizing on surface it has been observed that new polymorphic forms may exist near interface with substrate, which have structures different to those bulk. Such phases are termed as substrate‐induced (SIPs). The presence an SIP compound class can be crucial significance terms their physical properties. However, factors drive such process not...

A new 2:1 donor (D):acceptor (A) mixed-stacked charge-transfer (CT) cocrystal comprising isometrically structured dicyanodistyrylbenzene-based D and molecules is designed synthesized. Uniform 2D-type morphology manifested by the exquisite interplay of intermolecular interactions. In addition to its appealing structural features, unique optoelectronic properties are unveiled. Exceptionally high photoluminescence quantum yield (ΦF ≈ 60%) realized non-negligible oscillator strength S1...

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...

A combined experimental and theoretical approach, consisting of lattice phonon Raman spectroscopy density functional theory (DFT) calculations, is proposed as a tool for dynamics characterization polymorph phase identification. To illustrate the reliability method, spectra two polymorphs molecule 2,7-dioctyloxy[1]benzothieno[3,2-b]benzothiophene are investigated. We show that DFT calculations vibrations based on known crystal structures, including many-body dispersion van der Waals (MBD-vdW)...

The persistence of the acid⋯amide heterodimer and effect methyl substitution on short strong O–H⋯O hydrogen bond is investigated in urea methylurea di-carboxylic acid molecular complexes. Temperature dependent structural changes are also reported utilising X-ray neutron diffraction tandem.

Control over thin film growth (e.g., crystallographic orientation and morphology) is of high technological interest as it affects several physicochemical material properties, such chemical affinity, mechanical stability, surface morphology. The effect process parameters on the molecular organization perfluorinated polymers deposited via initiated vapor deposition (iCVD) has been previously reported. We showed that tendency poly(1H,1H,2H,2H-perfluorodecyl acrylate) (pPFDA) to organize in an...

The carboxylic acid dimer is a frequently observed intermolecular association used in crystal engineering and design, which can show proton disorder across its hydrogen bonds. Proton benzoic dimers dynamic, temperature-dependent process whose reported occurrence still relatively rare. A combination of variable temperature X-ray neutron diffraction has been applied to demonstrate the effect local crystalline environment on both degree onset 3,5-dinitrobenzoic dimers. Dimers have significantly...

Elastic scattering mechanisms dominate the charge transport in crystalline metals, resulting a characteristic increase conductivity at low temperatures. However, disorder – arising, for example, from alloying can hamper and lead to decreased coherence among scattered electrons (i.e. inelastic scattering). This is typically situation non-crystalline metals. Likewise, conductive polymers are particularly prone defect states with carrier mobility electrical conductivity). We present first...

Film forming properties of semiconducting organic molecules comprising alkyl-chains combined with an aromatic unit have a decisive impact on possible applications in electronics. In particular, knowledge the film formation process terms wetting or dewetting, and precise control these processes, is high importance. present work, subtle effect temperature morphology structure dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) films deposited silica surfaces by spin coating investigated...

Abstract Despite the recent encouraging advances in achieving high‐performance organic field effect transistors employing meniscus‐guided processing techniques compatible with roll‐to‐roll manufacturing, there is still a very limited knowledge about how all coating parameters influence thin film electrical characteristics. Here, polymorphism and morphology of films semiconductor dibenzo‐tetrathiafulvalene blended polystyrene deposited by bar‐assisted meniscus shearing (BAMS) are investigated...

The phenomenon of solid-state proton migration within molecular complexes containing short hydrogen bonds is investigated in two dimethylurea–oxalic acid complexes. Extensive characterisation by both X-ray and neutron diffraction shows that along the bond can be induced these as a function temperature. This emphasises subtle features potential well such bonded complexes, intrinsically effect local crystalline environment. Based on findings, synthesis analysis series shown to route designing...

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...

Neutron specular reflectometry (SR) and off-specular scattering (OSS) are nondestructive techniques which, through deuteration, give a high contrast even among chemically identical species therefore highly suitable for investigations of soft-matter thin films. Through combination these two techniques, the former yielding density profile in direction normal to sample surface latter depth-resolved in-plane lateral structure, one can obtain quite detailed information on buried morphology length...

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...

A series of molecular complexes the proton sponge 1,8-bis(dimethylamino)naphthalene (DMAN) with monosubstituted halobenzoic acids are reported, illustrating designed exploitation characteristics to induce short, charge-assisted hydrogen bonds in a predictable and reproducible manner. In every case, DMAN molecule extracts from carboxylic acid group benzoic acid, as result which recurrent supramolecular unit between neutral deprotonated is formed, featuring an extremely strong O–H···O bond,...

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...

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

4-Phenoxyphenol is a simple organic molecule that crystallizes as porous material with channels running throughout the structure. The are constructed by 6-fold hydrogen bonded ring and can host solvent molecules incorporated during crystal growth, minimum channel diameter of 5.8–5.9 Å; each usually contains single per unit cell. shows surprising flexibility, being able both to breathe sustain its crystalline integrity even when grown empty pores. This particularly given remainder...

The origin of unknown polymorphic phases within thin films is still not well understood. This work reports on crystals the molecule terthiophene which were grown by thermal gradient crystallization using glass-plate substrates. crystalline domains displayed a plate-like morphology with an extended lateral size about 100 µm, but thickness only few µm. Specular X-ray diffraction patterns confirmed presence new polymorph terthiophene. Crystal structure solution from single crystal peeled film...

Herein, we describe the synthesis and characterization of a conjugated donor-acceptor copolymer consisting pyrrolopyridazinedione (PPD) acceptor unit, benzodithiophene (BDT) donor unit. The polymerization was done via Stille cross-coupling polycondensation. resulting PPD-BDT revealed an optical bandgap 1.8 eV good processability from chlorobenzene solutions. In organic solar cell in combination with PC70BM, polymer led to power conversion efficiency 4.5%. Moreover, performance evaluated...

Proflavine hemisulphate (3,6-diaminoacridine hydrate), crystallizes in the monoclinic space group P2t/c, with a= 12.703 (1), b= 19-940 (2), c=21.487 (2)/~, fl=92.24 (2) °, and Z= 16. The structure was solved by direct search methods. The asymmetric unit contains four proflavine molecules, two sulphate ions seven water molecules. structure refined to a final R of 0.074 for 4738 statistically significant reflexions, out total 5601 measured on diffractometer. proflavine rings have slight...

Abstract The presence of a substrate‐induced polymorph 2,7‐dioctyloxy[1]benzothieno[3,2‐ b ]benzothiophene is probed in microscopic crystals and thin films. Two experimental techniques are used: lattice phonon Raman IR spectroscopy. bulk crystal phase have an entirely different molecular packing, therefore, their spectra characteristic fingerprints the respective polymorphs. These can be unambiguously assigned to individual Drop‐cast spin‐coated films on solid substrates investigated...

Proton behavior within the hydrogen bond (HB) networks of five molecular complexes proton sponge DMAN and different organic acids is investigated by single-crystal neutron diffraction. The form with either 2:1 (acid:DMAN) or 1:1 stoichiometric ratios contain common structural motifs. All show transfer from an acid to DMAN, forming a DMANH+ moiety hydrogen-bonded dimers; halobenzoic have molecules linked short, strong, charge-assisted HBs, while all intramolecular N–H···N HB in DMANH+. atom...

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...