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1.
Adv Mater ; : e2407791, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39239995

RESUMO

Climate Change and Materials Criticality challenges are driving urgent responses from global governments. These global responses drive policy to achieve sustainable, resilient, clean solutions with Advanced Materials (AdMats) for industrial supply chains and economic prosperity. The research landscape comprising industry, academe, and government identified a critical path to accelerate the Green Transition far beyond slow conventional research through Digital Technologies that harness Artificial Intelligence, Smart Automation and High Performance Computing through Materials Acceleration Platforms, MAPs. In this perspective, following the short paper, a broad overview about the challenges addressed, existing projects and building blocks of MAPs will be provided while concluding with a review of the remaining gaps and measures to overcome them.

2.
J Chem Phys ; 135(19): 194501, 2011 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-22112086

RESUMO

We perform a systematic investigation of the resonance and vibrational properties of naphthyl-terminated sp carbon chains (dinaphthylpolyynes) by combined multi-wavelength resonant Raman (MWRR) spectroscopy, ultraviolet-visible spectroscopy, and Fourier-transform infrared (FT-IR) spectroscopy, plus ab initio density functional theory (DFT) calculations. We show that the MWWR and FT-IR spectroscopies are particularly suited to identify chains of different lengths and different terminations, respectively. By DFT calculations, we further extend those findings to sp carbon chains end-capped by other organic structures. The present analysis shows that combined MWRR and FT-IR provide a powerful tool to draw a complete picture of chemically stabilized sp carbon chains.


Assuntos
Carbono/química , Naftalenos/química , Poli-Inos/química , Teoria Quântica , Vibração
3.
J Chem Phys ; 131(17): 174711, 2009 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-19895039

RESUMO

In the framework of Langevin dynamics, we demonstrate clear evidence of the peculiar quantized sliding state, previously found in a simple one-dimensional boundary lubricated model [A. Vanossi et al., Phys. Rev. Lett. 97, 056101 (2006)], for a substantially less idealized two-dimensional description of a confined multilayer solid lubricant under shear. This dynamical state, marked by a nontrivial "quantized" ratio of the averaged lubricant center-of-mass velocity to the externally imposed sliding speed, is recovered, and shown to be robust against the effects of thermal fluctuations, quenched disorder in the confining substrates, and over a wide range of loading forces. The lubricant softness, setting the width of the propagating solitonic structures, is found to play a major role in promoting in-registry commensurate regions beneficial to this quantized sliding. By evaluating the force instantaneously exerted on the top plate, we find that this quantized sliding represents a dynamical "pinned" state, characterized by significantly low values of the kinetic friction. While the quantized sliding occurs due to solitons being driven gently, the transition to ordinary unpinned sliding regimes can involve lubricant melting due to large shear-induced Joule heating, for example at large speed.

4.
Nat Nanotechnol ; 13(3): 246-252, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29410499

RESUMO

Two-dimensional (2D) materials have emerged as promising candidates for next-generation electronic and optoelectronic applications. Yet, only a few dozen 2D materials have been successfully synthesized or exfoliated. Here, we search for 2D materials that can be easily exfoliated from their parent compounds. Starting from 108,423 unique, experimentally known 3D compounds, we identify a subset of 5,619 compounds that appear layered according to robust geometric and bonding criteria. High-throughput calculations using van der Waals density functional theory, validated against experimental structural data and calculated random phase approximation binding energies, further allowed the identification of 1,825 compounds that are either easily or potentially exfoliable. In particular, the subset of 1,036 easily exfoliable cases provides novel structural prototypes and simple ternary compounds as well as a large portfolio of materials to search from for optimal properties. For a subset of 258 compounds, we explore vibrational, electronic, magnetic and topological properties, identifying 56 ferromagnetic and antiferromagnetic systems, including half-metals and half-semiconductors.

5.
J Phys Chem B ; 114(46): 14834-41, 2010 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-20973472

RESUMO

We report a combined study on the synthesis, spectroscopic characterization, and theoretical modeling of a series of α,ω-dinaphthylpolyynes. We synthesized this family of naphthyl-terminated sp carbon chains by reacting diiodoacetylene and 1-ethynylnaphthalene under the Cadiot-Chodkiewicz reaction conditions. By means of liquid chromatography (HPLC), we separated the products and recorded their electronic absorption spectra, which enabled us to identify the complete series of dinaphthylpolyynes Ar-C(2n)-Ar (with Ar = naphthyl group and n = number of acetilenic units) with n ranging from 2 to 6. The longest wavelength transition (LWT) in the electronic spectra of the dinaphthylpolyynes red shifts linearly with n away from the LWT of the bare termination. This result is also supported by DFT-LDA simulations. Finally, we probed the stability of the dinaphthylpolyynes in a solid-state precipitate by Fourier-transform infrared spectroscopy and by differential scanning calorimetry (DSC).

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