Jordi Faraudo, Jordi S. Andreu, Carles Calero, Juan Camacho; Advanced Functional Materials, 22 January 2016 DOI: 10.1002/adfm.201504839
Self-assembly processes are very important in material sciences but are particularly difficult to predict quantitatively. This is the case for particulate magnetic materials in which field-induced self-assembly processes are essential. This article describes the recent advances in the development of predictive theoretical tools for the study of directed self-assembly of superparamagnetic colloids under magnetic fields. A practical view is presented of how to employ the new concepts (derived from thermodynamic theory) to predict the possible assembled structures from the properties of the colloids and thermodynamic conditions. Quantitative prediction of kinetics is also discussed for the cases in which equilibrium theory is not relevant. Finally, an outline of fundamental aspects of the theory is presented.
Tuneable and low cost molecular electronics
Predicting the Self-Assembly of Superparamagnetic Colloids under Magnetic Fields
When we speak of nanometric water films on surfaces we are speaking about a truly ubiquitous phenomenon in nature. All surfaces exposed to ambient conditions are covered by a thin film of water that affects or mediates surface chemistry, general physical-chemical processes on surfaces, and even solid–solid interactions.
Electrocrystallization of tetramethyl-bis(ethylenedithio)-tetrathiafulvalene (TM-BEDT-TTF) (1) as pure (S,S,S,S) and (R,R,R,R) enantiomers in the presence of (n-Bu4N)2(Mo6O19) and chloroform or bromoform afforded a series of four isostructural enantiopure radical cation salts [(S/R)-1]9(Mo6O19)5·(CHX3)2 (X = Cl, Br) crystallizing in the trigonal non-centrosymmetric space group R32.
The dramatic consequences that the orientation adopted by the molecular dipoles, in diverse arrays of chloroaluminum phthalocyanine (ClAlPc) on Au(111), have on the ulterior adsorption and growth of C60 are explored by means of an all scanning probe microscopy approach. The unidirectional downwards organization of the molecular dipoles at the first layer reduces charge transfer from the metal to C60. Imbalance between attractive and repulsive interactions of the fullerenes are crucial for their ordered supramolecular aggregation.
To date, crystallization studies conducted in space laboratories, which are prohibitively costly and unsuitable to most research laboratories, have shown the valuable effects of microgravity during crystal growth and morphogenesis. Herein, an easy and highly efficient method is shown to achieve space-like experimentation conditions on Earth employing custom-made microfluidic devices to fabricate 2D porous crystalline molecular frameworks.
Layered group V transition-metal trichalcogenides are paradigmatic low-dimensional materials providing an ever increasing series of unusual properties. They are all based on the same basic building units, one-dimensional MX3 (M = Nb, Ta; X = S, Se) trigonal-prismatic chains that condense into layers, but their electronic structures exhibit significant differences leading to a broad spectrum of transport properties, ranging from metals with one, two, or three charge density wave instabilities to semimetals with potential topological properties or semiconductors.