The phonon dispersion curves, infra-red and Raman spectra of SrCl₂

In Situ Determination of Speciation and Local Structure of NaCl–SrCl2 and LiF–ZrF4 Molten Salts

“…The Raman band correlates well within experimental error with that measured by Schreyer et al after annealing the SrCl 2 sample at 400 °C for 10 min ( v = 181.5 ± 1 cm). This too agreed well with that reported by a number of investigators. − A blue shift by a few wavenumbers suggests, relative to the SrCl 2 structure, that the 25 °C pre-melt Cl-mix solid has a decreased lattice parameter or compressed structure. Additionally, at all temperatures below the MP for this Cl-mix, the only observable band is assignable to the higher valent cation component, SrCl 2 .…”

Effect of XC functionals and dispersion corrections on the DFT‐computed structural and vibrational properties of SrCl2–NaCl and ZrF4–LiF

“…The experimental Raman and infrared spectra for SrCl 2 both have only one band occurring at 184 and 148 cm À1 , respectively. [58,59] The Raman band arises from the antiphase motion of the neighboring Cl À anions around the Sr 2+ cations. [60] Similarly, for the infrared spectra, this band is caused by the movement of cations in relation to the surrounding cage of the anions.…”

“…[60] Similarly, for the infrared spectra, this band is caused by the movement of cations in relation to the surrounding cage of the anions. [58] The frequencies of the vibrational modes can be described by…”

“…Based on the SrCl 2 structural and vibrational results, the following extrapolation can be assumed for SrX 2 (X = F, Cl, Br, I) halides: (i) The closest the crystal structure is predicted to that of experiment, the better agreement between the DFT-calculated vibrational spectra and F I G U R E 1 Raman (black) and infrared (red) spectra of SrCl 2 calculated using different exchange-correlation functionals. The dashed lines represent the experimental Raman and infrared spectra from Denham et al [58] and Hisano et al [59] The frequency of each band is written above (or next) to it in cm À1 their corresponding experimental measurements; (ii) the effect of temperature can be indirectly observed/predicted via DFT calculations, that is, the bigger the cell parameters, the longer the bonds (and subsequently, the weaker the bonds), resulting in lower frequencies, (iii) regardless of how the vibrational frequencies are calculated (i.e., finite difference vs. DFPT), the method developed by Fonari et al [22] can be used to include van der Waals interactions, and the results are accurate, and (iv) based on Equation (1), it can be expected how the vibrational frequencies change as a function of atomic weight as well as the differences between the electronegativities. For instance, SrF 2 should exhibit a higher vibrational frequencies compared with SrCl 2 since the bonding between Sr-F is stronger than that of Sr-Cl, and fluorine atoms are lighter compared with chlorine atoms.…”

Density functional study of the electronic structure and lattice dynamics of SrCl2

“…Recently, a full-potential linear muffin-tin orbital method has been used to investigate the electronic structure of SrCl 2 leading to the determination of ground state and elastic properties [16]. The phonon dispersion curves, infrared and Raman spectra of SrCl 2 were studied a long time ago [18]. Phonon dispersion curves of SrCl 2 have been measured at room temperature in the [001], [110], [111] directions using the inelastic neutron scattering technique [19].…”