Effect of Structural Anisotropy in High-Pressure R... - BV FAPESP
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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Effect of Structural Anisotropy in High-Pressure Reaction of Aniline

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Author(s):
Fanetti, Samuele [1, 2, 3] ; Nobrega, Marcelo M. [1, 4] ; Teixeira-Neto, Erico [5] ; Temperini, Marcia L. A. [4] ; Bini, Roberto [1, 2, 3]
Total Authors: 5
Affiliation:
[1] European Lab Nonlinear Spect LENS, Via Nello Carrara 1, I-50019 Sesto Fiorentino - Italy
[2] Univ Firenze, Dipartimento Chim, Via Lastruccia 3, I-50019 Sesto Fiorentino - Italy
[3] Ist Chim Composti OrganoMetall, Via Madonna Piano 10, I-50019 Florence - Italy
[4] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, CP 26077, BR-05513970 Sao Paulo - Brazil
[5] Brazilian Ctr Res Energy & Mat CNPEM, Brazilian Nanotechnol Natl Lab LNNano, BR-13083970 Campinas, SP - Brazil
Total Affiliations: 5
Document type: Journal article
Source: Journal of Physical Chemistry C; v. 122, n. 51, p. 29158-29164, DEC 27 2018.
Web of Science Citations: 2
Abstract

The pressure-induced reactivity of aromatic molecules in the crystal phase has been recently demonstrated to be a practicable route for the synthesis of crystalline nanothreads. The formation of these attracting materials is ascribed to stress anisotropy induced by uniaxial compression. In the case of aniline, the attainment of NH2-enriched carbon nanothreads above 30 GPa is related to the intrinsic crystal anisotropy due to the presence of strong directional H-bonds. Here, we have probed the reactivity of aniline crystal at lower pressure and higher temperature with the multifold purpose of testing the efficiency of H-bonds in ruling the crystal compressibility with increasing temperature; verifying the simple model based on the phonon assistance used in other cases to explain the crystal reactivity; and scaling down the synthesis of nanothreads. The reaction, monitored by infrared spectroscopy, is quantitative, but the product obtained is a hydrogenated graphitic carbon nitride. The simple model based on a reactivity driven by the lattice phonons is capable of accounting for the reactivity in the entire pressure range, whereas the difference in the products synthesized at pressures below and above 20 GPa is accounted for by the anisotropic compressibility of the unit cell due to the strong directional H-bonds. As a result, it is concluded that independent from the different products obtained, the high-pressure reactivity in aniline is always topochemical. (AU)

FAPESP's process: 12/13119-3 - Vibrational spectroscopy in condensed phases
Grantee:Mauro Carlos Costa Ribeiro
Support Opportunities: Research Projects - Thematic Grants
FAPESP's process: 14/15107-8 - High pressure Raman spectroscopy, from aromatics amines to conducting polymers.
Grantee:Marcelo Medre Nobrega
Support Opportunities: Scholarships in Brazil - Post-Doctoral
FAPESP's process: 15/09763-2 - High pressure synthesis and reactivity of aniline and polyaniline-gold composites
Grantee:Marcelo Medre Nobrega
Support Opportunities: Scholarships abroad - Research Internship - Post-doctor