scholarly journals The Role of Low-Energy Electron Interactions in cis-Pt(CO)2Br2 Fragmentation

2021 ◽  
Vol 22 (16) ◽  
pp. 8984
Author(s):  
Maicol Cipriani ◽  
Styrmir Svavarsson ◽  
Filipe Ferreira da Silva ◽  
Hang Lu ◽  
Lisa McElwee-White ◽  
...  

Platinum coordination complexes have found wide applications as chemotherapeutic anticancer drugs in synchronous combination with radiation (chemoradiation) as well as precursors in focused electron beam induced deposition (FEBID) for nano-scale fabrication. In both applications, low-energy electrons (LEE) play an important role with regard to the fragmentation pathways. In the former case, the high-energy radiation applied creates an abundance of reactive photo- and secondary electrons that determine the reaction paths of the respective radiation sensitizers. In the latter case, low-energy secondary electrons determine the deposition chemistry. In this contribution, we present a combined experimental and theoretical study on the role of LEE interactions in the fragmentation of the Pt(II) coordination compound cis-PtBr2(CO)2. We discuss our results in conjunction with the widely used cancer therapeutic Pt(II) coordination compound cis-Pt(NH3)2Cl2 (cisplatin) and the carbonyl analog Pt(CO)2Cl2, and we show that efficient CO loss through dissociative electron attachment dominates the reactivity of these carbonyl complexes with low-energy electrons, while halogen loss through DEA dominates the reactivity of cis-Pt(NH3)2Cl2.

2010 ◽  
Vol 22 (8) ◽  
pp. 084006 ◽  
Author(s):  
Mahesh Rajappan ◽  
Lin L Zhu ◽  
Jizhou Wang ◽  
Graeme Gardner ◽  
Kevin Bu ◽  
...  

2020 ◽  
Vol 22 (11) ◽  
pp. 6100-6108 ◽  
Author(s):  
Filipe Ferreira da Silva ◽  
Rachel M. Thorman ◽  
Ragnar Bjornsson ◽  
Hang Lu ◽  
Lisa McElwee-White ◽  
...  

In this study, we present experimental and theoretical results on dissociative electron attachment and dissociative ionisation for the potential FEBID precursor cis-Pt(CO)2Cl2.


2019 ◽  
Vol 2019 (11) ◽  
Author(s):  
T Sonoda ◽  
I Katayama ◽  
M Wada ◽  
H Iimura ◽  
V Sonnenschein ◽  
...  

Abstract An in-flight separator performs the important role of separating a single specific radioactive isotope (RI) beam from the thousands of RI beams produced by in-flight fission as well as projectile fragmentation. However, when looking at ``separation'' from a different viewpoint, more than 99% of simultaneously produced RI beams are just eliminated in the focal plane slits or elsewhere in the separator. In order to enhance the effective usability of the RIKEN in-flight separator BigRIPS, we have been developing an innovative method: parasitic laser ion source (PALIS), which implements parasitic low-energy RI beam production by saving eliminated RI beams during BigRIPS experiments. In this paper, we present the expected benefits and feasibility for the PALIS concept and the results of the first stopping examination for high-energy RI beams in the gas cell.


2014 ◽  
Vol 10 (S313) ◽  
pp. 97-98
Author(s):  
Kenji Yoshida

AbstractSymmetric and triangle-shaped flux variability in X-ray and gamma-ray light curves is observed from many blazars. We derived the X-ray spectrum changing in time by using a kinetic equation of high energy electrons. Giving linearly changing the injection of low energy electrons into accelerating and emitting region, we obtained the preliminary results that represent the characteristic X-ray variability of the linear flux increase with hardening in the rise phase and the linear decrease with softening in the decay phase.


2003 ◽  
Vol 18 (15) ◽  
pp. 1037-1042 ◽  
Author(s):  
F. I. COOPERSTOCK ◽  
V. FARAONI

Traditional derivations of the Planck mass ignore the role of charge and spin in general relativity. From the Kerr–Newman null surface and horizon radii, quantized charge and spin dependence are introduced in an extended Planck scale of mass. Spectra emerge with selection rules dependent upon the choice of Kerr–Newman radius to link with the Compton wavelength. The appearance of the fine structure constant suggests the possibility of a variation in time of the extended Planck mass, which may be much larger than the variation in the traditional one. There is a suggestion of a connection with the α value governing high-energy radiation in Z-boson production and decay.


2016 ◽  
Vol 113 (10) ◽  
pp. 2654-2659 ◽  
Author(s):  
Moh Lan Yap ◽  
Thomas Klose ◽  
Fumio Arisaka ◽  
Jeffrey A. Speir ◽  
David Veesler ◽  
...  

Bacteriophage T4 consists of a head for protecting its genome and a sheathed tail for inserting its genome into a host. The tail terminates with a multiprotein baseplate that changes its conformation from a “high-energy” dome-shaped to a “low-energy” star-shaped structure during infection. Although these two structures represent different minima in the total energy landscape of the baseplate assembly, as the dome-shaped structure readily changes to the star-shaped structure when the virus infects a host bacterium, the dome-shaped structure must have more energy than the star-shaped structure. Here we describe the electron microscopy structure of a 3.3-MDa in vitro-assembled star-shaped baseplate with a resolution of 3.8 Å. This structure, together with other genetic and structural data, shows why the high-energy baseplate is formed in the presence of the central hub and how the baseplate changes to the low-energy structure, via two steps during infection. Thus, the presence of the central hub is required to initiate the assembly of metastable, high-energy structures. If the high-energy structure is formed and stabilized faster than the low-energy structure, there will be insufficient components to assemble the low-energy structure.


2021 ◽  
Vol 129 (12) ◽  
pp. 1471
Author(s):  
И.В. Чернышова ◽  
Е.Э. Контрош ◽  
О.Б. Шпеник

Abstract– The interactions of low-energy electrons (<20 eV) with D-ribose molecules, namely, electron scattering and dissociative attachment, are studied. The results of these studies showed that the fragmentation of D-ribose molecules occurs effectively even at an electron energy close to zero. as well as in the energy range 5.50–9.50 eV. In the total cross section of electron scattering by molecules, resonance features at energies of 5.00–9.00 eV in the region of formation of ionic fragments C3H4O2–, C2H3O2–, OH–, associated with the destruction of molecular heterocycles, were experimentally discovered for the first time. The correlation of the features observed in the scattering and dissociative electron attachment cross sections is analyzed.


Sign in / Sign up

Export Citation Format

Share Document