Search results for "Germanium"

Zirconocene [Cp2Zr] synthon and benzynezirconocene complexes as tools in main group element chemistry

1998

Abstract Interactions between zirconocene or benzyne zirconocene and unsaturated species incorporating main group elements lead to a variety of new metallaheterocycles. Efficient new methodologies of regiospecific syntheses of mono-, bi-, or tricyclic systems incorporating phosphorus, nitrogen, selenium, antimony, germanium or tin are reported.

Anchimer beschleunigte Homolysen, V. Thermische und Fluoridionen‐katalysierte Umlagerungen von Benzyl)‐[9‐(trimethylgermyl)‐9‐fluorenyl]‐ether

1980

Anchimerically Enhanced Homolyses, V. Fluoride Ion Catalysed Rearrangements of Benzyl 9-(Trimethylgermyl)-9-fluorenyl Ether The thermal rearrangement (homolysis) of the germanium compound 1d into 4d is considerably slower than that of the analogous Si compound 1c. Thus, a correlation is suggested between the velocity of the rearrangement and the strength of the new bond to oxygen. The rearrangement 1d4d is also induced by fluoride ions at room temperature.

Über Germanium‐haltige Heterocyclen, I. Darstellung und Charakterisierung der 8‐Ring‐Verbindungen 2,2‐Dichlor‐1,3,6,2‐trithiagermocan und 5,5‐Dichlor…

1975

Die Darstellung der Titelverbindungen 3 und 4 wird beschrieben. 1H-NMR-, IR-, Raman- und Massenspektren werden zusammen mit den entsprechenden Spektren der analogen Zinnverbindungen 1 und 2 diskutiert. In Losungen der 8-Ringe 1 - 4 besteht ein Gleichgewicht zwischen zwei chiralen Wanne-Sessel-Konformeren uber eine achirale Sessel-Sessel-Konformation. Fur 1 wird ferner eine Berry-Pseudoration am trigonal-bipyramidal koordinierten Sn-Atom angenommen. Versuche zur Darstellung von analogen Si-Verbindungen werden erwahnt. On Heterocyclic Systems Containing Germanium, I. Synthesis and Investigation of the Eighy-membered Rings 2,2-Dichloro-1,3,6,2-trithiagermocane and 5,5-Dichloro-1,4,6,5-oxadithi…

Electrochemistry and germanium porphyrins in nonaqueous media. Reactions of water and hydroxide ligands associated with (P)Ge(ClO4)2 and (P)Ge(OH)2, …

1988

Heterocyclic systems containing tin(IV)—XIII [1]. Possible ceasing or inversion of the structuraltrans influence during the course of a bimolecular n…

1997

Abstract In the series of the heterocycles X[(CH2)3]2SnR2 (16 newly synthesized compounds and two taken from the literature) and in the germanium analog BuiN[(CH2)3]2GeCl2, the donor group X (= NMe, NBz, NBui, NPri, O, S) intramolecularly attacks the Lewis acidic atoms Sn or Ge. Eight structure determinations (and, in addition, 2 taken from the literature) are compared. The nucleophilic attack at Sn is stronger for the ligands R2 =Cl2 than for the more electronegative R2 = (OSiPh3)2. Overall the familiartrans influence holds: simultaneous approach of X and weakening of the ligand R (trans). In three cases of subtly graded donor strength a slight inversion or ceasing is observed: shorter dis…

Light harvesting with Ge quantum dots embedded in SiO2 and Si3N4

2014

Cataloged from PDF version of article. Germanium quantum dots (QDs) embedded in SiO2 or in Si3N4 have been studied for light harvesting purposes. SiGeO or SiGeN thin films, produced by plasma enhanced chemical vapor deposition, have been annealed up to 850 degrees C to induce Ge QD precipitation in Si based matrices. By varying the Ge content, the QD diameter can be tuned in the 3-9 nm range in the SiO2 matrix, or in the 1-2 nm range in the Si3N4 matrix, as measured by transmission electron microscopy. Thus, Si3N4 matrix hosts Ge QDs at higher density and more closely spaced than SiO2 matrix. Raman spectroscopy revealed a higher threshold for amorphous-to-crystalline transition for Ge QDs e…

Radiopurity control in the NEXT-100 double beta decay experiment: procedures and initial measurements

2013

[EN] The "Neutrino Experiment with a Xenon Time-Projection Chamber" (NEXT) is intended to investigate the neutrinoless double beta decay of Xe-136, which requires a severe suppression of potential backgrounds. An extensive screening and material selection process is underway for NEXT since the control of the radiopurity levels of the materials to be used in the experimental set-up is a must for rare event searches. First measurements based on Glow Discharge Mass Spectrometry and gamma-ray spectroscopy using ultra-low background germanium detectors at the Laboratorio Subterraneo de Canfranc (Spain) are described here. Activity results for natural radioactive chains and other common radionucl…

Investigating the mechanical properties of GeSn nanowires.

2019

Germanium tin (GeSn) has been proposed as a promising material for electronic and optical applications due to the formation of a direct band-gap at a Sn content >7 at%. Furthermore, the ability to manipulate the properties of GeSn at the nanoscale will further permit the realisation of advanced mechanical devices. Here we report for the first time the mechanical properties of GeSn nanowires (7.1-9.7 at% Sn) and assess their suitability as nanoelectromechanical (NEM) switches. Electron microscopy analysis showed the nanowires to be single crystalline, with surfaces covered by a thin native amorphous oxide layer. Mechanical resonance and bending tests at different boundary conditions were use…

Conductive films of ordered nanowire arrays

2004

peer-reviewed High-density, ordered arrays of germanium nanowires have been synthesised within the pores of mesoporous thin films (MTFs) and anodized aluminium oxide (AAO) matrices using a supercritical fluid solution-phase inclusion technique. Conductive atomic force microscopy (C-AFM) was utilised to study the electrical properties of the nanowires within these arrays. Nearly all of the semiconductor nanowires contained within the AAO substrates were found to be conducting. Additionally, each individual nanowire within the substrate possessed similar electrical properties demonstrating that the nanowires are continuous and reproducible within each pore. C-AFM was also able to probe the co…

Electronic Band Transitions in γ-Ge3N4

2021

This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Support from Estonian Research Council grant PUT PRG 619 is gratefully acknowledged. The multi-anvil experiments at LMV were supported by the French Government Laboratory of Excellence initiative no ANR-10-LABX-0006, the Région Auvergne and the European Regional Development Fund (ClerVolc Contribution Number 478).