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Pandulphi Collenucii Pisaurensis Quatuor
No full textCollenuccio, Pandolfo Apologi quattuor ... III. Alithia [EST: Alithia]. VD16 C 4564Collenuccio, Pandolfo Apologi quattuor ... IIII. Bombarda [EST: Bombarda]. VD16 C 4566Collenuccio, Pandolfo Apologi quattuor ... II. Misopenes [EST: Misopenes]. VD16 C 4569Vorlageform des Erscheinungsvermerks: Argentorati in ædibus Matthiæ Schurerij An. M. D. XI.Bibliografischer Nachweis: VD16C 456
Pandulphi Collenucii Pisaurensis Quatuor
No full textCollenuccio, Pandolfo Apologi quattuor ... III. Alithia [EST: Alithia]. VD16 C 4564Collenuccio, Pandolfo Apologi quattuor ... IIII. Bombarda [EST: Bombarda]. VD16 C 4566Collenuccio, Pandolfo Apologi quattuor ... II. Misopenes [EST: Misopenes]. VD16 C 4569Vorlageform des Erscheinungsvermerks: Argentorati in ædibus Matthiæ Schurerij An. M. D. XI.Bibliografischer Nachweis: VD16C 456
Tris(pyrazol-1-yl)borate and tris(pyrazol-1-yl)methane: A DFT study of their different binding capability toward Ag(I) and Cu(I) cations
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Inorganica Chimica Acta
Volume 362, Issue 12, 15 September 2009, Pages 4358-4364
Tris(pyrazol-1-yl)borate and tris(pyrazol-1-yl)methane: A DFT study of their different binding capability toward Ag(I) and Cu(I) cations (Article)
Casarin, M.acd , Forrer, D.ad, Garau, F.a, Pandolfo, L.ad, Pettinari, C.b, Vittadini, A.cd
a Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
b Dipartimento di Scienze Chimiche, Camerino, Italy
c Istituto di Scienze Molecolari, CNR, Padova, Italy
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Abstract
Density functional theory has been used to study the electronic structure of [M(tp)] and [M(tpm)]+ conformers (M = Cu, Ag; tp = tris(pyrazol-1-yl)borate anion, tpm = tris(pyrazol-1-yl)methane) and the energetics of their interconversions. Results for the free tp ligand are similar to those of tpm [M. Casarin, D. Forrer, F. Garau, L. Pandolfo, C. Pettinari, A. Vittadini, J. Phys. Chem. A 112 (2008) 6723], indicating an intrinsic instability of the tripodal conformation (κ3-like). This points out that, though frequently observed, the κ3-coordinative mode is unlikely to be directly achieved through the interaction of M(I) with the κ3-like tp/tpm conformer. Analogously to the [M(tpm)]+ molecular ions, the energy barrier for the κ2-[M(tp)] → κ3-[M(tp)] conversion is computed to be negligible. Though κn-[M(tp)] and κn-[M(tpm)]+ (n = 1, 2, 3) have similar metal-ligand covalent interactions, the negative charge associated to the tp ligand makes the M-tp bonding stronger
Pio II e Sigismondo Pandolfo Malatesta
No full textSi esamina il contrastato rapporto fra il papa Pio II e Sigismondo Pandolfo Malatesta, accusato di eresia, nel contesto degli interessi nepotistici del pontefice e del quadro ipolitico internazionale del tempo
Tris(pyrazol-1-yl)borate and Tris(pyrazol-1-yl)methane: A DFT Study of Their Different Binding Capability Toward Ag(I) and Cu(I) Cations
No full textDensity functional theory has been used to study the electronic structure of [M(tp)] and [M(tpm)]+ conformers (M = Cu, Ag; tp = tris(pyrazol-1-yl)borate anion, tpm = tris(pyrazol-1-yl)methane) and the energetics of their interconversions. Results for the free tp ligand are similar to those of tpm [M. Casarin, D. Forrer, F. Garau, L. Pandolfo, C. Pettinari, A. Vittadini, J. Phys. Chem. A 112 (2008) 6723], indicating an intrinsic instability of the tripodal conformation (k3-like). This points out that, though frequently observed, the k3-coordinative mode is unlikely to be directly achieved through the interaction of M(I) with the k3-like tp/tpm conformer. Analogously to the [M(tpm)]+ molecular ions, the energy barrier for the k2-[M(tp)] → k3-[M(tp)] conversion is computed to be negligible. Though kn-[M(tp)] and kn-[M(tpm)]+ (n = 1, 2, 3) have similar metal–ligand covalent interactions, the negative charge associated to the tp ligand makes the M-tp bonding stronger
Further Insights into the Structure of [M(η2(C,C‘)-C3O2)(PPh3)2] (M = Ni, Pd, Pt) by Quasi-Relativistic Density Functional Calculations and Solid-State CP/MAS NMR
No full textThe molecular and electronic structures of [M(η2(C,C‘)-C3O2)(PPh3)2] (M = Ni, Pd, Pt) have been investigated by means of quasi-relativistic gradient-corrected density functional calculations and solid-state CP/MAS NMR spectroscopy. Theoretical outcomes are consistent with a square-planar coordination around the central metal atom and are in very good agreement with the bonding scheme emerging from IR and NMR data
Dinuclear copper(II) trispyrazolylborate derivatives with bridging pyrazolate anions
No full textTwo mu-pyrazolate dicopper derivatives, [Cu2(mu-pz)2(Tpx)2] [Tpx = Tp, tris(pyrazol-1-yl)borate or Tp*, tris(3,5-dimethylpyrazol-1-yl)borate], prepared either by treating the trinuclear [Cu3(mu3-OH)(mu-pz) 3(RCOO)2LxLy] species (R = H, Me, Et, Pr; L, L'= H2O, MeOH, EtOH, Hpz; Hpz = pyrazole) with an excess of M[Tpx] (M = Na, K) or by reaction of Cu(RCOO)2 with equimolar amounts of Hpz and M[Tpx], have been characterized by IR, magnetic susceptibility measurements and single crystal XRD structural determination
Epidemiology of preeclampsia in a Sicilian Hospital
No full textMultivariate logistic regression has shown that the following variables are independent risk factors for preeclampsia: age, BMI, parity, and twin pregnancy. Moreover, preeclampsia is significantly associated with the examined clinical effects, confirming itself as a leading cause of maternal-fetal morbidity
Volume thermal expansion along the jadeite–diopside join
No full textAn in situ single-crystal high-temperature X-ray diffraction study was performed on clinopyroxene crystals along the jadeite, (NaAlSi2O6 Jd)–diopside (CaMgSi2O6 Di) join. In particular, natural samples of jadeite, diopside, P2/n omphacite and three C2/c synthetic samples with intermediate composition (i.e., Jd80, Jd60, Jd40) were investigated. In order to determine the unit-cell volume thermal expansion coefficient (αV), the unit-cell parameters for all these compositions have been measured up to c.a. 1,073 K. The evolution of the unit-cell volume thermal expansion coefficient (αV) along the Jd–Di join at different temperatures has been calculated by using a modified version of the equation proposed by Holland and Powell (J Metamorph Geol 16(3):309–343, 1998). The equation aV(303K,1bar) = 2.68(3) × 10-5 + [1.1(1) × 10-8 × XJd]-[7.1(1.7) × 10-10 × X2 Jd] obtained from the αV at room-T (i.e., αV303K,1bar) allows us to predict the room-T volume thermal expansion for Fe-free C2/c clinopyroxenes with intermediate composition along the binary join Jd-Di. The observed αV value for P2/n omphacite αV(303K,1bar) = 2.58 (5) × 10-5 K-1 was compared with that recalculated for disordered C2/c omphacite published by Pandolfo et al. (Phys Chem Miner 1–10, 2012) [αV(303K,1bar) = 2.4(5) × 10-5 K-1]. Despite the large e.s.d.’s for the latter, the difference of both values at room-T is small, indicating that convergent ordering has practically no influence on the room-T thermal expansion. However, at high-T, the smaller thermal expansion coefficient for the C2/c sample with respect to the P2/n one with identical composition could provide further evidence for its reduced stability relative to the ordered one
THE ORGANOMETALLIC CHEMISTRY OF CARBON SUBOXIDE
No full textCarbon suboxide, C3O2, reacts with a great variety of organometallic compounds, yielding, with organosilicon and organoaluminum, sililation and carboalumination products, respectively. Insertion reactions of C=C are performed with compounds having M-H, M-OR, M-NR2, M-PR2 bonds, giving mono-meta derivatives (ketenyl) or di-metal derivatives. Ketenyl, ketenylidene and carbonyl complexes are also obtained
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