Resolution of the Absorption Spectrum of Solvated Electrons

1972 ◽  
Vol 57 (5) ◽  
pp. 2122-2129 ◽  
Author(s):  
Roberto Lugo ◽  
Paul Delahay
1998 ◽  
Vol 76 (4) ◽  
pp. 411-413
Author(s):  
Yixing Zhao ◽  
Gordon R Freeman

The energy and asymmetry of the optical absorption spectrum of solvated electrons, es- , change in a nonlinear fashion on changing the solvent through the series HOH, CH3OH, CH3CH3OH, (CH3)2CHOH, (CH3)3COH. The ultimate, quantum-statistical mechanical, interpretation of solvated electron spectra is needed to describe the solvent dependence. The previously reported optical spectrum of es- in tert-butanol was somewhat inaccurate, due to a small amount of water in the alcohol and to limitations of the infrared light detector. The present note records the remeasured spectrum and its temperature dependence. The value of the energy at the absorption maximum (EAmax) is 155 zJ (0.97 eV) at 299 K and 112 zJ (0.70 eV) at 338 K; the corresponding values of G epsilon max (10-22 m2 aJ-1) are 1.06 and 0.74. These unusually large changes are attributed to the abnormally rapid decrease of dielectric permittivity of tert-butanol with increasing temperature. The band asymmetry at 299 K is Wb/Wr = 1.8.Key words: optical absorption spectrum, solvated electron, solvent effects, tert-butanol, temperature dependence.


Author(s):  
P. Krebs

Some years ago Jay-Gerin and Ferradini attempted to establish a correlation between the optical absorption spectrum and the mobility of excess electrons in various polar solvents (J. Chem. Phys.


1971 ◽  
Vol 49 (20) ◽  
pp. 3398-3401 ◽  
Author(s):  
D. C. Walker ◽  
S. C. Wallace

From the optical absorption spectrum observed by a sub-nanosecond pulse radiolysis method it is concluded that irradiated pure liquid formamide (dielectric constant = 109) does not yield solvated electrons with lifetimes >10−11 s. In formamide–water mixtures the hydrated electron is formed in low yield and the position of the absorption band of eaq− is not altered by changing the composition. Apparently formamide reacts much more rapidly with thermalized electrons than it does with hydrated electrons. The latter may be formed in formamide–water mixtures due to aggregates of water molecules.


2019 ◽  
Vol 107 (3) ◽  
pp. 305
Author(s):  
Mengmei Geng ◽  
Yuting Long ◽  
Tongqing Liu ◽  
Zijuan Du ◽  
Hong Li ◽  
...  

Surface-enhanced Raman Scattering (SERS) fiber probe provides abundant interaction area between light and materials, permits detection within limited space and is especially useful for remote or in situ detection. A silver decorated SERS fiber optic probe was prepared by hydrothermal method. This method manages to accomplish the growth of silver nanoparticles and its adherence on fiber optic tip within one step, simplifying the synthetic procedure. The effects of reaction time on phase composition, surface plasmon resonance property and morphology were investigated by X-ray diffraction analysis (XRD), ultraviolet-visible absorption spectrum (UV-VIS absorption spectrum) and scanning electron microscope (SEM). The results showed that when reaction time is prolonged from 4–8 hours at 180 °C, crystals size and size distribution of silver nanoparticles increase. Furthermore, the morphology, crystal size and distribution density of silver nanoparticles evolve along with reaction time. A growth mechanism based on two factors, equilibrium between nucleation and growth, and the existence of PVP, is hypothesized. The SERS fiber probe can detect rhodamin 6G (R6G) at the concentration of 10−6 M. This SERS fiber probe exhibits promising potential in organic dye and pesticide residue detection.


Sign in / Sign up

Export Citation Format

Share Document