Structure, disorder, and phase transition in ternary crystals of anthracene, phenanthrene, and tetracyanobenzene, AxPh1−xTCNB

Abstract

Articles you may be interested inInfluence of anthracene doping on the order-disorder phase transition in phenanthrene AIP Conf. Proc. 1512, 44 (2013); 10.1063/1.4790902 Anisotropic displacive to order-disorder crossover of the orientational phase transition in anthracene tetracyanobenzene crystal J. Chem. Phys. 90, 7346 (1989); 10.1063/1.456214Static disorder in crystals of the anthracene-tetracyanobenzene charge transfer complex Phase transition effects: A crystallographic characterization of the temperature dependency of the crystal structure of the 1:1 charge transfer complex between anthracene and tetracyanobenzene in the temperature range 297 to 119 K The structure of ternary, charge-transfer crystals of anthracene, phenanthrene, and tetracyanobenzene, A x Ph 1Ϫx TCNB, in a wide range of concentrations has been studied. We have focused on the problem of substitutional and orientational disorder of anthracene and phenanthrene molecules and its influence on the orientational instability. The crystal structure determination has been performed at room temperature and 120 K, and the refinement procedures allowed us to determine the orientational disorder for different concentrations. The phase diagram for the orientational phase transition with symmetry change, C2/m to P2 1 /a, has been determined and a critical concentration (x c ϭ0.74) was found. The disorder and the phase diagram has been successfully modeled by a minimization of the crystal energy using the ''split molecule'' concept and the virtual crystal approximation to mimic both orientational and substitutional disorders. The ternary crystals, their structure, disorder, and phase transitions are well understood in terms of a competition between orientational disorder of anthracene molecules and local stresses created by the substitutional disorder ͑with statistical orientations͒ of phenanthrene molecules. A possibility for an existence of molecular orientational glassy state is suggested for concentrations below the critical one.

Dual Reactivity of 3a,6a-Diaza-1,4-diphosphapentalene: π-Donor versus n-Donor

“…The organocyanide acceptor tetracyanobenzene (TCNB) is known to form charge transfer complexes with multiple organic donors. Among these are complexes with condensed aromatic compounds, , aromatic and conjugated amines, − and sulfur-containing heterocyclic compounds (tetrathiafulvalene and its derivatives). − Despite the fact that a large number of complexes of organic and heterocyclic compounds with TCNB are already known, no π-complexes of azaphospholes with TCNB [or other π-acceptors of this class (TCNE and TCNQ)] have been described in the literature. This can be partially explained by the lack of donor properties of azaphospholes.…”

Spin Properties and Electronic Structure in Organic Ternary Crystals

“…Later on, ambipolar charge transport behavior was observed in charge transfer cocrystals, bis­(ethylenedithiolo)­tetrathiafulvalene (BEDT-TTF)-TCNQ, which opens a door for the study of optics-related properties. Fabricating and modifying the optical properties of charge transfer cocrystals have been realized to present a tunable multicolor emission via cocrystallization. ,, A multistep charge transfer-induced coassembly was also developed to prepare various multicomponent charge transfer cocrystals, where the emission colors can be changed from red to blue. − Recently, Lee et al have fabricated highly efficient dual color-emitting and white light-emitting ternary charge transfer crystals through tuning the interactions between the donors or acceptors, − which provides an alternative approach to construct miniaturized luminescent devices. Hu et al involved two different intermolecular interactions, arene-perfluoroarene and charge transfer interactions, to prepare ternary charge transfer crystals with tunable emission colors. , Furthermore, the hydrogen bonding- and the halogen bonding-dependent interactions also determine the molecular configuration and macroscopic properties of ternary crystals. , In organic charge transfer ternary crystals, D 1 –A 1 , D 2 –A 1 and D 1 –A 2 interactions are tightly related to the desired properties of ternary crystals.…”