Search results for "coinage"
showing 10 items of 18 documents
Reappraising Schmidpeter's bis(iminophosphoranyl)phosphides: coordination to transition metals and bonding analysis
2020
The synthesis and characterization of a range of bis(iminophosphoranyl)phosphide (BIPP) group 4 and coinage metals complexes is reported. BIPP ligands bind group 4 metals in a pseudo fac-fashion, and the central phosphorus atom enables the formation of d0–d10 heterobimetallic complexes. Various DFT computational tools (including AIM, ELF and NCI) show that the phosphorus–metal interaction is either electrostatic (Ti) or dative (Au, Cu). A bridged homobimetallic Cu–Cu complex was also prepared and its spectroscopic properties were investigated. The theoretical analysis of the P–P bond in BIPP complexes reveals that (i) BIPP are closely related to ambiphilic triphosphenium (TP) cations; (ii) …
COVID-19 and its linguistic variants from Miss Rona to Boomer Remover
2022
The COVID-19 pandemic has had an enormous impact on everyday language and has led to unprecedented linguistic innovation and lexical explosion, ranging from the medicalisation of everyday language to the creation of new word formations that have defined new situations and overcome the fear of an unknown disease. In this paper, after briefly introducing the main linguistic features of English neologisms created to define changes in life style during the pandemic, a survey of the main English monikers coined to rename COVID-19 will be given taking into account the most recent studies on the subject.
Poder Real Africano. Propaganda y legitimación de Juba I (ca. 60-46 a. C.) a través de sus emisiones helenísticas
2019
Este artículo tiene como objetivo presentar un estado de la cuestión acerca de las acuñaciones monetarias del rey númida Juba I. Históricamente nos encontramos ante la Segunda Guerra Civil Romana mantenida entre Pompeyo y Julio César (49-45 a. C.), donde Juba I apoya al «bando pompeyano». Las monedas de Juba I son producto de dicho acontecimiento y tienen su explicación en el pago de tropas contratadas. Además, las leyendas monetarias se insertan dentro de la propaganda e inciden en la posterior legitimación del trono númida, en manos de Juba I. This paper aims to present a state of the question about the coins struck by Juba I, king of Numidia. Historically we find ourselves before the Sec…
Benzothiazolethione complexes of coinage metals: from mononuclear complexes to clusters and polymers
2019
Abstract The reactions of 2(3H)-benzothiazolethione (Hbtt) with [AuCl(tetrahydrothiophene)] and CuBr2 were studied, and found to yield a tetranuclear cluster compound [Au(btt)]4 [1] and a polymeric structure [CuBr(btt-btt)]n.nTHF (2). Crystallographic and spectroscopic methods were used for the characterization. In 1, the monoanionic ligand acted as a bidentate bridging N,S-donor giving a molecular cluster structure of an asymmetric coordination isomer. In the formation of 2, the ligand was dimerized by forming a S–S bond after deprotonation, and coordination via nitrogen donors to metal atoms took place leading to a polymeric structure. To clarify the diversity of reactions of Hbtt with co…
Bond stretching and redox behavior in coinage metal complexes of the dichalcogenide dianions [(SPh2P)2CEEC(PPh2S)2]2- (E=S, Se): diradical character …
2011
The metathetical reactions of a) [Li(tmeda)](2)[(S)C(PPh(2)S)(2)] (Li(2)·3c) with CuCl(2) and b) [Li(tmeda)](2)[(SPh(2)P)(2)CSSC(PPh(2)S)(2)] (Li(2)·4c) with two equivalents of CuCl both afford the binuclear Cu(I) complex {Cu(2)[(SPh(2)P)(2)CSSC(PPh(2)S)(2)]} (5c). The elongated (C)S-S(C) bond (ca. 2.54 and 2.72 A) of the dianionic ligand observed in the solid-state structure of 5c indicate the presence of diradical character as supported by theoretical analyses. The treatment of [Li(tmeda)](2)[(SPh(2)P)(2)CSeSeC(PPh(2)S)(2)] (Li(2)·4b) and Li(2)·4c with AgOSO(2)CF(3) produce the analogous Ag(I) derivatives, {Ag(2)[(SPh(2)P)(2)CEEC(PPh(2)S)(2)]} (6b, E=Se; 6c, E=S), respectively. The disele…
Du monnayage au crypto-monnayage
2020
Minting Techniques in Currencies and Cryptocurrencies. Over the past ten years, the creation of bitcoin and other cryptocurrencies has renewed the debate on the nature of money. This paper discusses the comparison between cryptocurrencies and coins : after describing their ideological and technical foundations, we explain the reasons why the reference to metals is often invoked. We then detail the techniques of minting, the processes of marking, and the question of seigniorage.
Una llamativa pieza reacuñada de la ceca Carissa (Cortijo de Carija, Cádiz)
2014
Se documenta un curioso ejemplar pesado cuya noved ad, además de la pieza en sí, la representan los dos glóbulos observables detrás de la cabeza galeada y que encontramos en el anverso. Estos glóbulos, concebidos como marca de v alor, pudieron ser del cuño original del anverso o, en su caso, de una pieza anterior a una reacuñación; aunque, finalmente, cabría otra posibilidad y que descartamos en este artículo: un nuevo valor a añadir, como un “As” o una “Unidad”, para la entonces ceca gaditana de Carissa . We present a curious heavy specimen whose novelty resides, besides the piece itself, in the two noticeable pellets behind the galley pro w on obverse. These pellets, conceived as a mark o…
Dramme, didrammi e tetradrammi di Panormos e a legenda ṣyṣ nel V secolo a.C.: aggiornamenti e riflessioni intorno alle sequenze dei conî
2019
The main objective of this essay is to comment upon the modes of production and the datings of the 5th century BC non-fractional silver coinage bearing the Greek legend ΠΑΝΟΡΜΟΣ (and variants) and the Punic legend ṣyṣ. The reconstruction of the die sequences published by G. Kenneth Jenkins in 1971 and its recent updates will be discussed in detail. As far as the identification of the issuing authority and of the minting place of the coins with legend ṣyṣ is concerned, for a long time to the center of the scientific research interests, only the inferences made from an analysis of the die sequence have been taken into consideration.
Reactivity of antitumor coinage metal-based N-heterocyclic carbene complexes with cysteine and selenocysteine protein sites
2021
Abstract The reaction of the antitumor M(I)-bis-N-heterocyclic carbene (M(I)-NHC) complexes, M = Cu, Ag, and Au, with their potential protein binding sites, i.e. cysteine and selenocysteine, was investigated by means of density functional theory approaches. Capped cysteine and selenocysteine were employed to better model the corresponding residues environment within peptide structures. By assuming the neutral or deprotonated form of the side chains of these amino acids and by considering the possible assistance of an external proton donor such as an adjacent acidic residue or the acidic component of the surrounding buffer environment, we devised five possible routes leading to the binding o…
2019
Energy-level alignment at organic-metal interfaces plays a crucial role for the performance of organic electronic devices. However, reliable models to predict energetics at strongly coupled interfaces are still lacking. We elucidate contact formation of 1,2,5,6,9,10-coronenehexone (COHON) to the (1 1 1)-surfaces of coinage metals by means of ultraviolet photoelectron spectroscopy, x-ray photoelectron spectroscopy, the x-ray standing wave technique, and density functional theory calculations. While for low COHON thicknesses, the work-functions of the systems vary considerably, for thicker organic films Fermi-level pinning leads to identical work functions of 5.2 eV for all COHON-covered meta…