Ion association of alkali and alkaline earth metal azides in dimethylsulfoxide. Infrared spectrometry and ab initio calculations

Raman band shape analysis of cyanate-anion ionic liquids

“…1 and the first row of Table 1 that the vibrational frequency of the totally symmetric mode, ω CN , increases in the order In the case of molten salts, it is well-known that the anion vibrational frequency increases with the polarizing power of the cation [13,40]. The polarizing power of a cation, P, can be simply defined by the ratio between charge, z, and ionic radius, a, but a more refined definition includes the ionization potential I, P = I / (5z 0.27 a 1/2 ) [41]. It is instructive to compare ω CN observed in ionic liquids and literature data available for inorganic salts.…”

Electric properties of the azide ion calculated with a systematic sequence of Gaussian-type basis sets

“…What is more, experimental estimates have been deduced from measurements in dense environments. In the most recent paper by Le Borgne et al [4] the mean polarizability of the azide ion has been obtained by refractive index and density measurements on aqueous solutions of NaN 3 and finally aðN À 3 Þ ¼ aðNaN 3 Þ À aðNa þ Þ. Nevertheless, the data in Table 6 advance a consistent picture of the azide ion, as a molecule with a large polarizability anisotropy and a large quadrupole moment.…”

“…Conversion factors to SI units are: energy, 1 E h = 4.3597482 · 10 À18 J; length, 1 a 0 = 0.529177249 · 10 À10 m; quadrupole moment, 1 e a 2 0 ¼ 4:486554 Â 10 À40 C m 2 ; hexadecapole moment, 1 e a 4 0 ¼ 1:256363 Â 10 À60 C m 4 and dipole polarizability, 1 e 2 a 2 0 E À1 h ¼ 1:648778 Â 10 À41 C 2 m 2 J À1 . Hereafter, property values are given as pure numbers, that is H=e a 2 0 , U=e a 4 0 and a ab =e 2 a 2 0 E À1 h .…”

“…Frech and Decius [3] extracted the polarizability of N À 3 from crystal measurements on sodium azide. A more recent paper by Le Borgne et al [4] reported values for both the mean and the anisotropy of the dipole polarizability deduced from refractive index measurements on aqueous solutions of sodium azide and Rayleigh diffusion measurements. The mean polarizability determined by the above efforts in dense environments shows important variation.…”

A novel intermolecular potential to describe the interaction between the azide anion and carbon nanotubes

“…The most important parameters are the atomic polarizabilities, which are used to determine the and r m values for V ilj , as well as appearing directly in the induction potential. The nitrogen atomic polarizability is obtained from the experimental total mean polarizability of the azide anion [89],ᾱ = 4.65Å 3 , which was distributed on the three atoms according to their partial charges, resulting in a value of 1.9Å 3 for the external atoms (charges q 1 = q 3 = −0.56 atomic units (au)) and a value of 0.85Å 3 for the internal one (charge q 2 = +0.12 au). The polarizability of the hydrogen atoms was taken from Ref.…”