1 H- 31 P CPVC NMR method under Very Fast ...
Type de document :
Article dans une revue scientifique
URL permanente :
Titre :
1 H- 31 P CPVC NMR method under Very Fast Magic Angle Spinning for analysis of dipolar interactions and dynamics processes in the crystalline phosphonium tetrafluoroborate salts
Auteur(s) :
Paluch, Piotr [Auteur]
Trebosc, Julien [Auteur]
Amoureux, Jean-Paul [Auteur]
Potrzebowski, Marek J. [Auteur]
Trebosc, Julien [Auteur]
Amoureux, Jean-Paul [Auteur]
Potrzebowski, Marek J. [Auteur]
Titre de la revue :
Solid State Nuclear Magnetic Resonance
Numéro :
87
Pagination :
96-103
Date de publication :
2017-10
Discipline(s) HAL :
Chimie/Chimie inorganique
Résumé en anglais : [en]
We present an NMR methodology which can be used to study the dynamical processes occurring in organophosphorus compounds that belong to the group of the organic ionic plastic crystals (OIPCs). As model samples we employed ...
Lire la suite >We present an NMR methodology which can be used to study the dynamical processes occurring in organophosphorus compounds that belong to the group of the organic ionic plastic crystals (OIPCs). As model samples we employed two phosphonium tetrafluoroborate salts; (t-Bu)3PH+BF4− (1) and (Me)3PH+BF4− (2). Both samples possess in their structures direct H-P bonds, and both undergo complex thermal processes in the solid state, forming below the melting point three or four phases, respectively. 1H-31P CPVC (Cross-Polarization Variable Contact) measurements were performed under Very Fast Magic Angle Spinning with speed equal to 50 or 60 kHz, in order (i) to establish the hydrogen-phosphorus dipolar couplings, and (ii) to correlate the dipolar splitting values with molecular motions of the cation. Our project is divided into three sections. In the first part we present DSC studies of (1) and (2), to verify whether these samples fulfill the requirements that define them as OIPC. The second part is dedicated to a discussion of the theoretical aspects of 1H-31P CPVC and especially an analysis of the influence of different parameters, e.g. CSA31P, H-H mismatch, rf-inhomogeneity, dipolar truncation, and the type of dynamics through the motionally averaged <ηD> asymmetry value on the NMR response. The third part shows experimental 1H-31P CPVC data and applicability of these measurements to study H-P distances and dynamics. The complex molecular motion for sample (2), including rotation and diffusion, versus temperature is then postulated on the bases of the changes of H-P dipolar splitting.Lire moins >
Lire la suite >We present an NMR methodology which can be used to study the dynamical processes occurring in organophosphorus compounds that belong to the group of the organic ionic plastic crystals (OIPCs). As model samples we employed two phosphonium tetrafluoroborate salts; (t-Bu)3PH+BF4− (1) and (Me)3PH+BF4− (2). Both samples possess in their structures direct H-P bonds, and both undergo complex thermal processes in the solid state, forming below the melting point three or four phases, respectively. 1H-31P CPVC (Cross-Polarization Variable Contact) measurements were performed under Very Fast Magic Angle Spinning with speed equal to 50 or 60 kHz, in order (i) to establish the hydrogen-phosphorus dipolar couplings, and (ii) to correlate the dipolar splitting values with molecular motions of the cation. Our project is divided into three sections. In the first part we present DSC studies of (1) and (2), to verify whether these samples fulfill the requirements that define them as OIPC. The second part is dedicated to a discussion of the theoretical aspects of 1H-31P CPVC and especially an analysis of the influence of different parameters, e.g. CSA31P, H-H mismatch, rf-inhomogeneity, dipolar truncation, and the type of dynamics through the motionally averaged <ηD> asymmetry value on the NMR response. The third part shows experimental 1H-31P CPVC data and applicability of these measurements to study H-P distances and dynamics. The complex molecular motion for sample (2), including rotation and diffusion, versus temperature is then postulated on the bases of the changes of H-P dipolar splitting.Lire moins >
Langue :
Anglais
Audience :
Internationale
Vulgarisation :
Non
Établissement(s) :
ENSCL
CNRS
Centrale Lille
Univ. Artois
Université de Lille
CNRS
Centrale Lille
Univ. Artois
Université de Lille
Collections :
Équipe(s) de recherche :
RMN et matériaux inorganiques (RM2I)
Date de dépôt :
2019-09-25T14:06:20Z