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Chemical bonding and reactions in molecular crystals at high pressure

English title Chemical bonding and reactions in molecular crystals at high pressure
Applicant Macchi Piero
Number 162861
Funding scheme Project funding (Div. I-III)
Research institution Departement für Chemie und Biochemie Universität Bern
Institution of higher education University of Berne - BE
Main discipline Physical Chemistry
Start/End 01.10.2015 - 31.03.2019
Approved amount 429'978.00
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Keywords (7)

polymorphism; chemical bonding; high pressure; X-ray diffraction; solid state chemistry; crystallography; density functional theory

Lay Summary (Italian)

Lead
Applicare pressione ad un materiale significa modificare il suo stato termodinamico. Quando la pressione è sufficientemente elevata, si possono ottenere nuove fasi, ossia nuove forme solide del materiale che differiscono per arrangiamento di atomi e molecole (transizioni di fase) oppure per la topologia dei legami chimici (reazioni chimiche in stato solido).Lo scopo di questa ricerca è quello di scoprire nuove forme solide di materiali molecolari, prodotte attraverso la compressione dei solidi, o anche dei liquidi, stabili a pressione ambiente. Due aspetti sono particolarmente rilevanti: a) il meccanismo di formazione del nuovo materiale; b) le proprietà meccaniche, elettro-ottiche o magnetiche della nuova forma.La nostra indagine si concentra in particolare su materiali organici e organometallici, che siano molecolari a pressioni ambientali, oppure polimeri di coordinazione (composti da leganti organici e ioni metallici).
Lay summary

La pressione è una variabile termodinamica come la temperatura. Al loro variare, si modifica l’energia di un sistema, attraverso un cambiamento di energia interna e uno scambio di energia con l’ambiente. Mentre molte trasformazioni dei materiali sono ben conosciute in funzione della temperatura, molto meno si conosce delle reazioni o dei cambiamenti di fase che un solido (oppure un liquido) incontra aumentandone la pressione. Nuove ed inattese forme dei materiali sono state recentemente scoperte proprio grazie allo studio di sistemi inorganici sotto pressione. Meno studiati sono i materiali soffici, quali ad esempio i cristalli di molecole organiche o organometalliche e i polimeri di coordinazione, di cui ci occuperemo in questo progetto.

L’interesse principale del nostro progetto è lo studio delle trasformazione di questi sistemi. Quando la pressione viene aumentata, un materiale può subire una mutamento anche radicale, poiché lo stato energetico fondamentale viene modificato con la contaminazione di altri stati o il passaggio ad un altro stato. Questo può influire notevolmente sulle proprietà del materiale, in particolare quelle elettroniche, ottiche e magnetiche.

Studieremo sia trasformazioni di fase (ossia cambiamenti delle conformazioni molecolari associati a cambiamenti nell’impaccamento che modifichino la simmetria del cristallo) sia reazioni chimiche (ossia formazione di nuovi legami). Particolarmente importanti sono le reazioni che coinvolgono la trasformazione di un contatto intermolecolare in un legame chimico covalente, producendo polimeri a partire da semplici cristalli molecolari.

Per questo progetto di ricerca verranno impiegate sia metodiche sperimentali (diffrazione, spettroscopia e microscopia), sia teoriche (calcoli quanto-meccanici)

Ci attendiamo risultati significativi, con implicazioni in chimica dello stato solido, chimica organica e metallorganica e scienza dei materiali.

Direct link to Lay Summary Last update: 29.09.2015

Responsible applicant and co-applicants

Employees

Publications

Publication
Behind the Scenes of Group 4 Metallocene Catalysis: Examination of the Metal–Carbon Bond
Machat Martin R., Fischer Andreas, Schmitz Dominik, Vöst Marcel, Drees Markus, Jandl Christian, Pöthig Alexander, Casati Nicola P. M., Scherer Wolfgang, Rieger Bernhard (2018), Behind the Scenes of Group 4 Metallocene Catalysis: Examination of the Metal–Carbon Bond, in Organometallics, 37(16), 2690-2705.
Giant pressure dependence and dimensionality switching in a metal-organic quantum antiferromagnet
Wehinger Björn, Fiolka Christoph, Lanza Arianna, Scatena Rebecca, Kubus Marius, Grockowiak A, Coniglio W A, Graf D, Skulatos M, Chen J H, Gukelberger J, Casati Nicola, Zaharko Oksana, Macchi Piero, Krämer Karl, Tozer S, Mudry C, Normand B, Rüegg Christian (2018), Giant pressure dependence and dimensionality switching in a metal-organic quantum antiferromagnet, in Physical Review Letters, 121, 117201.
Exploring charge density analysis in crystals at high pressure. Data collection, data analysis and advanced modelling
Casati Nicola, Genoni Alessandro, Meyer Benjamin, Krawczuk Anna, Macchi Piero (2017), Exploring charge density analysis in crystals at high pressure. Data collection, data analysis and advanced modelling, in Acta Crystallographica Sect. B, 73, 584.
Investigation of the commensurate magnetic structure in the heavy-fermion compound CePt2In7 using magnetic resonant x-ray diffraction
Gauthier N., Wermeille D., Casati N., Sakai H., Baumbach R.E., Bauer E.D., White J.S. (2017), Investigation of the commensurate magnetic structure in the heavy-fermion compound CePt2In7 using magnetic resonant x-ray diffraction, in Phys. Rev. B , 96, 064414.
J(Si,H) Coupling Constants of Activated Si–H Bonds
Meixner Petra, Batke Kilian, Fischer Andreas, Schmitz Dominik, Eickerling Georg, Kalter Marcel, Ruhland Klaus, Montisci Fabio, Barquera-Lozada José E., Casati Nicola, Montisci Fabio, Macchi Piero, Scherer Wolfgang (2017), J(Si,H) Coupling Constants of Activated Si–H Bonds, in Journal of Physical Chmistry, A, 7219.
Reversible pressure pre-amorphization of a piezochromic metal–organic framework
Andrzejewski M., Casati N., Katrusiak A. (2017), Reversible pressure pre-amorphization of a piezochromic metal–organic framework, in Dalton Transactions, 46(43), 14795-14803.
Putting pressure on aromaticity along with in situ experimental electron density of a molecular crystal
Casati Nicola, Kleppe Annette, Jephcoat Andrew, Macchi Piero (2016), Putting pressure on aromaticity along with in situ experimental electron density of a molecular crystal, in Nature Communications, 7, 10901.

Collaboration

Group / person Country
Types of collaboration
Department of Physics, University of Augsburg Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
- Research Infrastructure
- Exchange of personnel
Institute of Solid State Chemistry, University of Novosibirsk Russia (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication
Department of Chemistry University of Milan Italy (Europe)
- in-depth/constructive exchanges on approaches, methods or results
- Publication

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
Meeting Of the Polish Crystallographic Association Poster BONDING AND ELECTRICAL CONDUCTIVITY IN POLYIODIDES UNDER EXTREME PRESSURE 27.06.2018 Wroclaw, Poland Poreba Tomasz;
Meeting Of the Polish Crystallographic Association Poster ODDZIAŁYWANIA METALOFILOWE W ŚCIŚNIĘTYCH KRYSZTAŁACH POLIMERÓW KOORDYNACYJNYCH 27.06.2018 Wroclaw, Poland Michal Andrzejewski;
55th meeting of the European High pressure Research Group Poster Weak donor-acceptor intermolecular interactions under pressure: the NO2∙∙∙NO2 case 03.09.2017 poznan, Poland Montisci Fabio; Lanza Arianna; Casati Nicola; Macchi Piero;
55th meeting of the European High pressure Research Group Talk given at a conference Chemistry at work under High pressure 03.09.2017 poznan, Poland Poreba Tomasz; Macchi Piero; Casati Nicola;
General Assembly and meeting of the International Union of Crystallography Talk given at a conference Weak donor-acceptor intermolecular interactions under pressure: the NO₂···NO₂ case. 21.08.2017 Hyderabad, India Lanza Arianna; Casati Nicola; Macchi Piero; Montisci Fabio;
General Assembly and Meeting of the International Union of Crystallography Talk given at a conference Binding guest molecules to frameworks: pressure-induced chemisorption in breathing MOFs 21.08.2017 Hyderabad, India Casati Nicola; Macchi Piero; Lanza Arianna;
Meeting of the Italian Crystallographic Association Talk given at a conference Material properties, chemical bonding and reactions in metal - organic crystals at high pressure 26.06.2017 Perugia, Italy Lanza Arianna;
Meeting of the Italian Crystallographic Association Talk given at a conference Chemical Bonding and reactions in molecular crystals at high pressure 26.06.2017 Perugia, Italy Macchi Piero;
Erice School of Crystallography "High-pressure crystallography: status artis and emerging opportunities" Poster Testing soft donor-acceptor intermolecular interactions with high pressure. 27.05.2016 Erice, Italy Lanza Arianna; Montisci Fabio;


Self-organised

Title Date Place
Meeting of the Swiss Crystallographic Association 12.09.2017 Geneva, Switzerland
General Assembly and meeting of the International Union of Crystallography 21.08.2017 Hyderabad, India

Awards

Title Year
3rd Poster Prize at the 60th meeting of the Polish Crystallographic Association, Wroclaw 27-29 June 2018 2018
Best presentation (Tomas Poreba) at the annual symposium of PhD students (University of Bern, Fribourg and Neuchatel) 2017
Poster Prize at the annual meeting of the Swiss Crystallographic Association (Geneva 12/09/2017) 2017
Prize for best PhD thesis by the Italian Crystallographic Association (Arianna Lanza) 2017
4th PANalytical Award (Arianna Lanza) http://www.panalytical.com/News/Winner-of-the-fourth-PANalytical-Award-Arianna-Lanza.htm 2016
Best presentation (Fabio Montisci) at the annual symposium of PhD students (University of Bern, Fribourg and Neuchatel) 2016
Prize for 3rd best poster presentation at the Erice School of Crystallography 2016 (Fabio Montisci) 2016

Associated projects

Number Title Start Funding scheme
177033 A dual wavelength X-ray single crystal diffractometer for accurate investigations at extreme conditions 01.08.2018 R'EQUIP
144534 Chemical bonding and reactions in molecular crystals at high pressure 01.10.2012 Project funding (Div. I-III)

Abstract

In the last decade, high-pressure crystallography made enormous progresses, especially in the previously unexplored field of organic and organo-metallic crystals. The techniques to apply pressure to materials and to investigate the structural changes have been further developed and standardized, which enabled more systematic studies and a broader spectrum of observations. The data, that can nowadays be collected, allow to speculate not only on the softer intermolecular interactions, heavily affected by compression, but also on the finer changes of a molecular geometry, that better reveal the mechanisms of molecular activation.Our previous research has contributed to foster this rapidly growing field, thanks especially to investigations of soft interactions (metal-metal and metal-ligand bonds in metal complexes and coordination polymers) and on the reactivity of organic molecules. In addition, we have recently started exploring transformations, which are kinetically controlled.The possibility to step-wise investigate the mechanism of a chemical reaction in the solid state is one of the most appealing outcomes of high-pressure crystallography, on which we plan to dedicate further efforts during this research project. In particular, we will focus on:a) nucleophilic/electrophilic interactions in the solid state, that may give rise to predictable reaction paths. This is a way to put into practice the concepts of crystal engineering, using pressure to obtain the reaction products.b) pre-reactive states of molecules, that anticipate the occurrence of a chemical reaction. Although small, changes of molecular structures are observable, especially with single crystal X-ray diffraction and provide enormous information on the reactivity of functional groups in molecules. c) non-equilibrium processes, that enrich the diversity of transformations. So far, we have applied this concept to simple phase transformations involving the rupture and the formation of intermolecular hydrogen bonds, but it could be as well adopted for pressure induced chemical reactions occurring in molecular crystals.d) pressure transmission media, which are fundamental in order to preserve good crystallinity of the samples. Because most of the fluids typically employed are hydrostatic only below 10 GPa, accurate structural investigations are not accessible for many reaction products, that require higher pressure to occur. Finding fluids that remain hydrostatic (or quasi-hydrostatic) above this limit would enable significant extension of the pressure range that can be investigated, without resorting on more expensive and difficult techniques (like He-loading).The outcome of this research project will further enrich the current knowledge of pressure induced solid-state transformations in molecular crystals, providing more insight into the reactivity of species and the products of chemical reactions.
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