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  1. Article ; Online: High-pressure structure and reactivity of crystalline bibenzyl: Insights and prospects for the synthesis of functional double-core carbon nanothreads.

    Agati, Milo / Romi, Sebastiano / Fanetti, Samuele / Bini, Roberto

    The Journal of chemical physics

    2023  Volume 159, Issue 24

    Abstract: The high-pressure synthesis of double-core nanothreads derived from pseudo-stilbene crystals represents a captivating approach to isolate within the thread chromophores or functional groups without altering its mechanical properties. These entities can ... ...

    Abstract The high-pressure synthesis of double-core nanothreads derived from pseudo-stilbene crystals represents a captivating approach to isolate within the thread chromophores or functional groups without altering its mechanical properties. These entities can be effectively utilized to finely tune optical properties or as preferential sites for functionalization. Bibenzyl, being isostructural with other members of this class, represents the ideal system for building co-crystals from which we can synthesize double-core nanothreads wherein bridging chromophores, such as the azo or ethylene moieties, are embedded in the desired concentration within a fully saturated environment. To achieve this, a critical step is the preliminary characterization of the high-pressure behavior of crystalline bibenzyl. We report here an accurate investigation performed through state-of-the-art spectroscopic techniques, Raman and Fourier transform infrared spectroscopy, and x-ray diffraction up to 40 GPa. Our findings reveal a strongly anisotropic compression of the crystal, which determines, at pressures between 1 and 2 GPa, consistent modifications of the vibrational spectrum, possibly related to a torsional distortion of the molecules. A phase transition is detected between 9 and 10 GPa, leading to a high pressure phase where, above 24 GPa, the nanothread formation is observed. However, the observed reaction was limited in extent and required significantly higher pressures in comparison to other members of the pseudo-stilbene family. This comprehensive study is imperative in laying the foundation for future endeavors, aiming to synthesize double-core nanothreads from pseudo-stilbene crystals, and provides crucial insights into the high-pressure behavior and phase transitions of crystalline bibenzyl.
    Language English
    Publishing date 2023-12-29
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3113-6
    ISSN 1089-7690 ; 0021-9606
    ISSN (online) 1089-7690
    ISSN 0021-9606
    DOI 10.1063/5.0174157
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Complexities in the structural evolution with pressure of water-ammonia mixtures.

    Berni, Selene / Scelta, Demetrio / Fanetti, Samuele / Bini, Roberto

    The Journal of chemical physics

    2023  Volume 158, Issue 18

    Abstract: The structural evolution with pressure of icy mixtures of simple molecules is a poorly explored field despite the fundamental role they play in setting the properties of the crustal icy layer of the outer planets and of their satellites. Water and ... ...

    Abstract The structural evolution with pressure of icy mixtures of simple molecules is a poorly explored field despite the fundamental role they play in setting the properties of the crustal icy layer of the outer planets and of their satellites. Water and ammonia are the two major components of these mixtures, and the crystal properties of the two pure systems and of their compounds have been studied at high pressures in a certain detail. On the contrary, the study of their heterogeneous crystalline mixtures whose properties, due to the strong N-H⋯O and O-H⋯N hydrogen bonds, can be substantially altered with respect to the individual species has so far been overlooked. In this work, we performed a comparative Raman study with a high spatial resolution of the lattice phonon spectrum of both pure ammonia and water-ammonia mixtures in a pressure range of great interest for modeling the properties of icy planets' interiors. Lattice phonon spectra represent the spectroscopic signature of the molecular crystals' structure. The activation of a phonon mode in plastic NH3-III attests to a progressive reduction in the orientational disorder, which corresponds to a site symmetry reduction. This spectroscopic hallmark allowed us to solve the pressure evolution of H2O-NH3-AHH (ammonia hemihydrate) solid mixtures, which present a remarkably different behavior from the pure crystals likely to be ascribed to the role of the strong H-bonds between water and ammonia molecules characterizing the crystallites' surface.
    Language English
    Publishing date 2023-05-08
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3113-6
    ISSN 1089-7690 ; 0021-9606
    ISSN (online) 1089-7690
    ISSN 0021-9606
    DOI 10.1063/5.0150639
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Exploring High-Pressure Polymorphism in Carbonic Acid through Direct Synthesis from Carbon Dioxide Clathrate Hydrate.

    Berni, Selene / Scelta, Demetrio / Romi, Sebastiano / Fanetti, Samuele / Alabarse, Frederico / Pagliai, Marco / Bini, Roberto

    Angewandte Chemie (International ed. in English)

    2024  Volume 63, Issue 22, Page(s) e202403953

    Abstract: Carbon dioxide ( ... ...

    Abstract Carbon dioxide (CO
    Language English
    Publishing date 2024-04-23
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202403953
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Structure–Reactivity Relationship in the High-Pressure Formation of Double-Core Carbon Nanothreads from Azobenzene Crystal

    Romi, Sebastiano / Fanetti, Samuele / Alabarse, Frederico / Bini, Roberto

    Journal of physical chemistry. 2021 July 29, v. 125, no. 31

    2021  

    Abstract: Saturated carbon nanothreads are one of the most attractive new materials produced under high pressure in the last years. Nanothreads can be considered as a monodimensional diamond; in fact, they preserve some of the mechanical properties of the diamond ... ...

    Abstract Saturated carbon nanothreads are one of the most attractive new materials produced under high pressure in the last years. Nanothreads can be considered as a monodimensional diamond; in fact, they preserve some of the mechanical properties of the diamond itself, like stiffness, but their intrinsic flexibility makes them excellent nanowires. Since their discovery, many advancements have been made, and nowadays, they can be obtained from the compression of several aromatic molecular crystals. However, it is often not clear why certain starting crystals give high-quality nanothreads while others do not or which are the best conditions for the synthesis in terms of pressure, temperature, compression rate, and reaction time. In other words, the mechanisms that allow their formation with respect to other byproducts are often unclear. This is an important piece of information that can be used for the design of a synthetic strategy for the production of functional materials with targeted characteristics, like conductivity and electro-optical properties, while preserving the mechanical ones. Here, we report an X-ray diffraction study in which we followed the transformation induced by the pressure of trans-azobenzene using polycrystalline samples compressed with and without a pressure-transmitting medium. With this approach, we were able to highlight the structural relations along the reactive path leading to double-core saturated carbon nanothreads. The features that we discovered could be common to all pseudo-stilbene crystals, a class of compounds isostructural to azobenzene and characterized by two phenyl rings connected by a variety of different linkers, thus representing excellent starting materials for the synthesis of functional nanothreads.
    Keywords X-ray diffraction ; carbon ; nanowires ; physical chemistry ; temperature
    Language English
    Dates of publication 2021-0729
    Size p. 17174-17182.
    Publishing place American Chemical Society
    Document type Article
    ISSN 1932-7455
    DOI 10.1021/acs.jpcc.1c04003
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: Accessing the Activation Mechanisms of Ethylene Photo-Polymerization under Pressure by Transient Infrared Absorption Spectroscopy

    Romi, Sebastiano / Fanetti, Samuele / Bini, Roberto

    Journal of physical chemistry. 2020 Aug. 26, v. 124, no. 37

    2020  

    Abstract: The ambient temperature photoinduced polymerization of compressed (P < 1 GPa) fluid ethylene was characterized by transient infrared absorption spectroscopy with a resolution of few nanoseconds, 3 orders of magnitude higher than previously reported. The ... ...

    Abstract The ambient temperature photoinduced polymerization of compressed (P < 1 GPa) fluid ethylene was characterized by transient infrared absorption spectroscopy with a resolution of few nanoseconds, 3 orders of magnitude higher than previously reported. The reaction has been studied under both one- and two-photon excitation evidencing in the latter case its occurrence only in the presence of different transition metal oxides. Their photocatalytic activity is ascribed to the stabilization of the excited biradicals through electron density exchange between the d orbitals of the metal and the π antibonding orbitals of ethylene which lengthens the lifetime of the biradicals. In both one- and two-photon activation cases the polymerization is characterized by an initial step distinguished by a molecularity of 0.15 ± 0.02 identified as the activation step of the reaction lasting, in the one-photon excitation case, a few hundreds of nanoseconds. Using pulsed excitation the reaction evolves toward a free radical polymerization only under one-photon excitation whereas the critical concentration of radicals required to propagate the reaction is never achieved in the two-photon excitation case. Comparison with continuous wave excitation unambiguously identifies in the average power released to the sample the key factor to drive quantitatively and qualitatively the polymerization.
    Keywords ambient temperature ; ethylene ; free radicals ; infrared spectroscopy ; photocatalysis ; physical chemistry ; polymerization
    Language English
    Dates of publication 2020-0826
    Size p. 8149-8157.
    Publishing place American Chemical Society
    Document type Article
    Note NAL-AP-2-clean
    ISSN 1520-5207
    DOI 10.1021/acs.jpcb.0c06244
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: Growth Dynamics of Crystalline Ar Hydrate

    Fanetti, Samuele / Scelta, Demetrio / Bini, Roberto

    Journal of physical chemistry. 2020 Apr. 13, v. 124, no. 18

    2020  

    Abstract: The formation of a clathrate hydrate crystal is characterized by several steps, each of them distinguished by a different structural arrangement and temporal duration. A precise definition of these different forms is a challenging task, because the ... ...

    Abstract The formation of a clathrate hydrate crystal is characterized by several steps, each of them distinguished by a different structural arrangement and temporal duration. A precise definition of these different forms is a challenging task, because the entirety of the formation dynamics spans over a time interval ranging from few nanoseconds to several days. Computational methods are powerful and essential to define the nucleation step, but they fail in providing a reliable picture of the long-range order establishment. On the other side, the experimental methods employed in the study of the growth dynamics usually monitor the hydrate growth at the interface with the fluid and thus are limited by the diffusion of the guest molecules through the newly formed hydrate phase. This problem is overcome here by the confinement of an argon hydrate sample in a sapphire anvil cell, allowing monitoring of the melting and crystallization of hydrates under moderate pressures by FTIR and Raman spectroscopies. This approach, besides providing a spectroscopic characterization of this hydrate, allowed the time windows characteristic of the formation of a macroscopic amorphous phase to be identified, possibly coincident with the so-called blob, and its rapid evolution toward the achievement of the local structure. Long-range ordering takes place on a longer time scale, most of it is realized in few hours but still evolving for weeks. No hints for supporting the so-called memory effect are gained through this study.
    Keywords Fourier transform infrared spectroscopy ; Raman spectroscopy ; argon (noble gases) ; computational methodology ; crystallization ; melting ; monitoring ; spectral analysis
    Language English
    Dates of publication 2020-0413
    Size p. 10159-10166.
    Publishing place American Chemical Society
    Document type Article
    ISSN 1932-7455
    DOI 10.1021/acs.jpcc.0c00386
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: Accessing the Activation Mechanisms of Ethylene Photo-Polymerization under Pressure by Transient Infrared Absorption Spectroscopy.

    Romi, Sebastiano / Fanetti, Samuele / Bini, Roberto

    The journal of physical chemistry. B

    2020  Volume 124, Issue 37, Page(s) 8149–8157

    Abstract: The ambient temperature photoinduced polymerization of compressed ( ...

    Abstract The ambient temperature photoinduced polymerization of compressed (
    Language English
    Publishing date 2020-09-09
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5207
    ISSN (online) 1520-5207
    DOI 10.1021/acs.jpcb.0c06244
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Towards custom built double core carbon nanothreads using stilbene and pseudo-stilbene type systems.

    Romi, Sebastiano / Fanetti, Samuele / Alabarse, Frederico / Mio, Antonio M / Haines, Julien / Bini, Roberto

    Nanoscale

    2022  Volume 14, Issue 12, Page(s) 4614–4625

    Abstract: Until recently, saturated carbon nanothreads were the missing tile in the world of low-dimension carbon nanomaterials. These one-dimensional fully saturated polymers possess superior mechanical properties by combining high tensile strength with ... ...

    Abstract Until recently, saturated carbon nanothreads were the missing tile in the world of low-dimension carbon nanomaterials. These one-dimensional fully saturated polymers possess superior mechanical properties by combining high tensile strength with flexibility and resilience. They can be obtained by compressing aromatic and heteroaromatic crystals above 15 GPa exploiting the anisotropic stress that can be achieved by the diamond anvil cell technique. Recently, double-core nanothreads were synthesized by compressing azobenzene crystals, achieving the remarkable result of preserving the azo group as a linker of the resulting double thread. Herein, we demonstrate the generality of these findings through the synthesis of double carbon nanothreads from
    Language English
    Publishing date 2022-03-24
    Publishing country England
    Document type Journal Article
    ZDB-ID 2515664-0
    ISSN 2040-3372 ; 2040-3364
    ISSN (online) 2040-3372
    ISSN 2040-3364
    DOI 10.1039/d1nr08188h
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Pressure-Induced Aggregation of Associating Liquids as a Driving Force Enhancing Hydrogen Bond Cooperativity.

    Hachuła, Barbara / Włodarczyk, Patryk / Jurkiewicz, Karolina / Grelska, Joanna / Scelta, Demetrio / Fanetti, Samuele / Paluch, Marian / Pawlus, Sebastian / Kamiński, Kamil

    The journal of physical chemistry letters

    2023  Volume 15, Issue 1, Page(s) 127–135

    Abstract: The behavior of hydrogen bonds under extreme pressure is still not well understood. Until now, the shift of the stretching vibration band of the X-H group (X = the donor atom) in infrared spectra has been attributed to the variation in the length of the ... ...

    Abstract The behavior of hydrogen bonds under extreme pressure is still not well understood. Until now, the shift of the stretching vibration band of the X-H group (X = the donor atom) in infrared spectra has been attributed to the variation in the length of the covalent X-H bond. Herein, we combined infrared spectroscopy and X-ray diffraction experimental studies of two H-bonded liquid hexane derivatives, i.e., 2-ethyl-1-hexanol and 2-ethyl-1-hexylamine, in diamond anvil cells at pressures up to the GPa level, with molecular dynamics simulations covering similar thermodynamic conditions. Our findings revealed that the observed changes in the X-H stretching vibration bands under compression are not primarily due to H-bond shortening resulting from increased density but mainly due to cooperative enhancement of H-bonds caused by intensified molecular clustering. This sheds new light on the nature of H-bond interactions and the structure of liquid molecular systems under compression.
    Language English
    Publishing date 2023-12-26
    Publishing country United States
    Document type Journal Article
    ISSN 1948-7185
    ISSN (online) 1948-7185
    DOI 10.1021/acs.jpclett.3c03037
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Modulating the H-bond strength by varying the temperature for the high pressure synthesis of nitrogen rich carbon nanothreads.

    Fanetti, Samuele / Santoro, Mario / Alabarse, Frederico / Enrico, Berretti / Bini, Roberto

    Nanoscale

    2020  Volume 12, Issue 8, Page(s) 5233–5242

    Abstract: Carbon nanothreads are among the most attractive new materials produced under high pressure conditions. Their synthesis can be achieved by compressing the crystals of aromatic molecules exploiting both the anisotropic stress produced by the ... ...

    Abstract Carbon nanothreads are among the most attractive new materials produced under high pressure conditions. Their synthesis can be achieved by compressing the crystals of aromatic molecules exploiting both the anisotropic stress produced by the unidirectional applied force and that intrinsic to the crystal arrangement. We explored here the transformation of pyridine into a nitrogen rich carbon nanothread crystal by varying the pressure and temperature conditions with the twofold purpose of disclosing the microscopic mechanism of transformation and optimizing the yield and quality of the produced crystalline nanothreads. The best conditions for the synthesis were identified in the 14-18 GPa range at temperatures between 400 and 500 K with a product yield greater than 30%. The comparison of experiments performed under different P-T conditions allowed us to understand the role of high temperature, which is necessary to weaken or even destroy the complex H-bond network characterizing the pyridine crystal and preventing the correct approach of the aromatic rings for nanothread formation. X-ray diffraction data confirm the excellent 2D hexagonal packing of the nanothreads over several tens of microns, whereas the sharp absorption lines observed in the IR spectrum strongly support a substantial order along the threads. Diffraction results suggest a polytwistane structure of the threads derived from a Diels-Alder [4 + 2] polymerization involving molecules arranged in a slipped parallel configuration along the pyridine crystal a and b axes. Electron microscopy evidences an arrangement of the nanothreads in bundles of tens of nanometers.
    Language English
    Publishing date 2020-02-19
    Publishing country England
    Document type Journal Article
    ZDB-ID 2515664-0
    ISSN 2040-3372 ; 2040-3364
    ISSN (online) 2040-3372
    ISSN 2040-3364
    DOI 10.1039/c9nr10716a
    Database MEDical Literature Analysis and Retrieval System OnLINE

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