0000000001303940
AUTHOR
Alfonso Venzo
New phosphazene-based chain extenders containing allyl and epoxide groups
In this paper we present the synthesis and the characterization of cyclophosphazenes substituted with allyl groups, their transformation in epoxide-containing cyclophosphazenes and the final utilization of these compounds as chain extenders in combination with polyamides. The reaction at high temperature of Nylon-6 with epoxy-functionalized cyclophosphazenes leads to the opening of the epoxy units by the action of both amino (--NH2) and carboxylic (--COOH) end-groups of the polymer to enhance the final molecular weight of this material. The consequences of this fact on the thermal, mechanical and visco-elastic properties of treated Nylon-6 have been also evaluated and compared to those of t…
Pt(II) nitrile complexes: New insights on old complexes from a combined experimental and theoretical study
Abstract The spectroscopic characterization of cis - and trans -[PtCl 2 (NCR) 2 ] (R = CH 3 , Ph, CH 2 Ph) was reported in solid state and solution phase. Moreover, the X-ray structures of cis -[PtCl 2 (NCCH 3 ) 2 ], cis - and trans -[PtCl 2 (NCPh) 2 ] were redetermined at low temperature. FT-IR and NMR showed a blue-shift and a slight shielding of the νCN and δ ( 13 C CN ) values, respectively, in a counterintuitive way with respect to the well known improved reactivity towards nucleophiles of nitriles ligands coordinated to platinum(II), when compared to their free forms. These spectroscopic behaviors were also confirmed by theoretical experiments at DFT level. Moreover, DFT approach show…
Au25(SEt)18 a nearly naked thiolate-protected Au25 cluster Struct. analysis by single crystal X-ray crystallograp. and electron nuclear double res
X-ray crystallography has been fundamental in discovering fine structural features of ultrasmall gold clusters capped by thiolated ligands. For still unknown structures, however, new tools capable of providing relevant structural information are sought. We prepared a 25-gold atom nanocluster protected by the smallest ligand ever used, ethanethiol. This cluster displays the electrochemistry, mass spectrometry, and UV-vis absorption spectroscopy features of similar Au25 clusters protected by 18 thiolated ligands. The anionic and the neutral form of Au25(SEt)18 were fully characterized by (1)H and (13)C NMR spectroscopy, which confirmed the monolayer's properties and the paramagnetism of neutr…
A magnetic look into the protecting layer of Au25 clusters
The field of molecular metal clusters protected by organothiolates is experiencing a very rapid growth. So far, however, a clear understanding of the fine interactions between the cluster core and the capping monolayer has remained elusive, despite the importance of the latter in interfacing the former to the surrounding medium. Here, we describe a very sensitive methodology that enables comprehensive assessment of these interactions. Pulse electron nuclear double resonance (ENDOR) was employed to study the interaction of the unpaired electron with the protons of the alkanethiolate ligands in four structurally related paramagnetic Au25(SR)0 18 clusters (R ¼ ethyl, propyl, butyl, 2-methylpro…
Gold Nanowired: A Linear (Au25)n Polymer from Au25 Molecular Clusters
Au25(SR)18 has provided fundamental insights into the properties of clusters protected by monolayers of thiolated ligands (SR). Because of its ultrasmall core, 1 nm, Au25(SR)18 displays molecular behavior. We prepared a Au25 cluster capped by n-butanethiolates (SBu), obtained its structure by single-crystal X-ray crystallography, and studied its properties both experimentally and theoretically. Whereas in solution Au25(SBu)18(0) is a paramagnetic molecule, in the crystal it becomes a linear polymer of Au25 clusters connected via single Au-Au bonds and stabilized by proper orientation of clusters and interdigitation of ligands. At low temperature, [Au25(SBu)18(0)]n has a nonmagnetic ground s…
Metal Doping of Au25(SR)18- Clusters : Insights and Hindsights
The structure, properties, and applications of atomically precise gold nanoclusters are the object of active research worldwide. Over the last few years, research has been also focusing on selective doping of metal nanoclusters through introduction of foreign-metal atoms. Doping has been studied for several clusters, especially the atomically precise Au25(SR)18. Doping has been carried out with noble metals, such as platinum, and less noble metals, such as cadmium and mercury, also because of the ease by which monodoping can be achieved with these metals. Previous studies, which relied extensively on the use of mass spectrometry and single crystal X-ray crystallography, led to assign the sp…
CCDC 1938197: Experimental Crystal Structure Determination
Related Article: Wenwen Fei, Sabrina Antonello, Tiziano Dainese, Alessandro Dolmella, Manu Lahtinen, Kari Rissanen, Alfonso Venzo, Flavio Maran|2019|J.Am.Chem.Soc.|141|16033|doi:10.1021/jacs.9b08228
CCDC 1938194: Experimental Crystal Structure Determination
Related Article: Wenwen Fei, Sabrina Antonello, Tiziano Dainese, Alessandro Dolmella, Manu Lahtinen, Kari Rissanen, Alfonso Venzo, Flavio Maran|2019|J.Am.Chem.Soc.|141|16033|doi:10.1021/jacs.9b08228
CCDC 984217: Experimental Crystal Structure Determination
Related Article: Tiziano Dainese, Sabrina Antonello, José A. Gascón, Fangfang Pan, Neranjan V. Perera, Marco Ruzzi, Alfonso Venzo, Alfonso Zoleo, Kari Rissanen, and Flavio Maran|2014|ACS Nano|8|3904|doi:10.1021/nn500805n
CCDC 1938193: Experimental Crystal Structure Determination
Related Article: Wenwen Fei, Sabrina Antonello, Tiziano Dainese, Alessandro Dolmella, Manu Lahtinen, Kari Rissanen, Alfonso Venzo, Flavio Maran|2019|J.Am.Chem.Soc.|141|16033|doi:10.1021/jacs.9b08228
CCDC 1938198: Experimental Crystal Structure Determination
Related Article: Wenwen Fei, Sabrina Antonello, Tiziano Dainese, Alessandro Dolmella, Manu Lahtinen, Kari Rissanen, Alfonso Venzo, Flavio Maran|2019|J.Am.Chem.Soc.|141|16033|doi:10.1021/jacs.9b08228
CCDC 998586: Experimental Crystal Structure Determination
Related Article: Marco De Nardi, Sabrina Antonello, De-en Jiang, Fangfang Pan, Kari Rissanen, Marco Ruzzi, Alfonso Venzo, Alfonso Zoleo, Flavio Maran|2014|ACS Nano|8|8505|doi:10.1021/nn5031143
CCDC 1453036: Experimental Crystal Structure Determination
Related Article: Mikhail Agrachev, Sabrina Antonello, Tiziano Dainese, José A. Gascón, Fangfang Pan, Kari Rissanen, Marco Ruzzi, Alfonso Venzo, Alfonso Zoleo, Flavio Maran|2016|Chemical Science|7|6910|doi:10.1039/C6SC03691K
CCDC 1938195: Experimental Crystal Structure Determination
Related Article: Wenwen Fei, Sabrina Antonello, Tiziano Dainese, Alessandro Dolmella, Manu Lahtinen, Kari Rissanen, Alfonso Venzo, Flavio Maran|2019|J.Am.Chem.Soc.|141|16033|doi:10.1021/jacs.9b08228
CCDC 1427512: Experimental Crystal Structure Determination
Related Article: Tiziano Dainese, Sabrina Antonello, José A. Gascón, Fangfang Pan, Neranjan V. Perera, Marco Ruzzi, Alfonso Venzo, Alfonso Zoleo, Kari Rissanen, and Flavio Maran|2014|ACS Nano|8|3904|doi:10.1021/nn500805n
CCDC 1938196: Experimental Crystal Structure Determination
Related Article: Wenwen Fei, Sabrina Antonello, Tiziano Dainese, Alessandro Dolmella, Manu Lahtinen, Kari Rissanen, Alfonso Venzo, Flavio Maran|2019|J.Am.Chem.Soc.|141|16033|doi:10.1021/jacs.9b08228
CCDC 1938192: Experimental Crystal Structure Determination
Related Article: Wenwen Fei, Sabrina Antonello, Tiziano Dainese, Alessandro Dolmella, Manu Lahtinen, Kari Rissanen, Alfonso Venzo, Flavio Maran|2019|J.Am.Chem.Soc.|141|16033|doi:10.1021/jacs.9b08228