The electron affinity of Na 2KSb,Na 2KSb+Cs and(Na 2KSb+Cs)+Sb+Cs is 0.70～0.91 eV,0.35～0.41 eV and 0.33 eV respective1y. The difference of the electron affinity reflects difference of photo cathode preparation technology.
Their band gaps (Eg), electron affinity (E_A) and ionization potentials (P_I) calculated are 2.51-2.82 eV, 2.69-3.62 eV and 5.41-5.82 eV, respectively, indicating that compounds are good candidates as electroluminescent materials with good hole-transporting property.
Compared to D-π-A-π-D compounds, the intermolecular charge transfer (ICT) of D-π-A-π-A compounds increased with the enhancement of the electron affinity (E_A), which might result in high two-photon absorption cross-section.
Our preliminary results indicated that alternating addition of Sb and K may determine whether Na_2KSb compound is the p-or n-conducting type and that Cs sensitization may reduce its electron affinity and extend the spectral response cut-off wavelength.
Systematic theoretical methods have been used to study the thermochemical properties of NH 2,NH 2 +,NH 2 - ,such as dissociation energy(DE),electron affinity(EA),ionization energy(IE),proton affinity(PE) and atomization energy(AE). These methods involve Gaussian n methods: G1,G2,G2 (MP2) and CBS n methods: CBS 4,CBS q,CBS Q,CBS APNO.
Systematic theoretical methods have been used to study thermochemical properties of NH,NH +,NH -,such as dissociation energy(DE),electron affinity(EA),ionization energy(IE),proton affinity(PE)and atomization energy(AE). These methods involve Gaussian n methods:G1,G2,G2(MP2)and CBS n methods:(CBS 4,CBS q,CBS Q,CBS APNO).
On the basis of it, a novel PPV derivative poly(2-pentyloxy-3, 5-dibromine-1, 4-phenylene vinylene) (PPDBPV) carrying on both electron donating group and electron withdrawing group is prepared to improve the electron affinity of PPV. The monomers are polymerized under Gilch dehydrochlorination conditions.
Gold and silver havedramatically different properties, for example, in color, ionization energy, stable oxidationstate, electron affinity and formation of two atoms molecule and negative oxidation statecompound.
The results of vertical ionization protential(VIP) and vertical electron affinity(VEA) indicate that fullerene—barbituric acid remains most properties of C_(60) , but it is less stable and higher reactive than C_(60) .
Softness and hardness scale U of atoms is estimated and predicted more precisely together with their ionization potential P and electron affinity Q by density functional theory (DFT) combined with either local density approximation (LDA) or with further global corrections for exchange included self-consistently (LDB: LDA-GCE) as well as modified Slater transition-state method (MST) and definite-differentiation method (DDM) under partial consideration of relativistic effects.
At atmospheric pressure in a low-temperature plasma containing electronegative components with significant electron affinity (of the order of or greater than 1.5 eV) considerable negative ion concentrating may occur.
The possibility of using fullerenes as matrices with a high electron affinity is shown.
Electron affinity and substituent effects in radical anions
The photoemission of electrons from a p+-GaAs surface with negative electron affinity was studied experimentally at 4.2 K.
The refraction of thermalized photoelectrons emitted into vacuum from p+-GaAs-(Cs,O) with a negative electron affinity was observed.