Infrared absorption of SeO and SeO impurity ions in KCl and KBr crystals

Abstract

In the temperature range 120 to 300 O K a study has been made of the infrared absorption spectra of KC1 and KBr single crystals doped with Se0:-and Se0:-anions. It is shown that the Se0,2-anions in these matrices form complexes SeO:-. M2+ of symmetry Cp, with cations M2+ (M2' -Ca2', Sr2-, Ba") similar t o the complexes SO,"-N2+ and CrOi--M2-observed earlicr. A lowering of the local symmetry results in the splitting of VJF) vibration of the tetrahedral anion SeO:-. An identification of bands and their fine structure assumed to be isotropic was made in the infrared absorption spectra of the complex SeO2-. RIPf. The existence of similar complexes SeOi-* MZ7 was assumed in KBr and KCI lattices doped with Se0;-In connection with the quartet structure of infrared absorption spectra in the vibration region YJE) of the Se0;-anion.

Surface Charging in CdSe Quantum Dots: Infrared and Transient Absorption Spectroscopy

“…The (lateral) SeO stretch exhibits a very strong IR line 27 with a frequency of 901 cm −1 . Similarly, matrix isolated SeO 3 2− has a SeO stretching vibration 28 at 790 cm −1 . On the basis of these known Se−O stretch frequencies, it is reasonable to assign the 800 cm −1 feature seen in these spectra to a Se−O bond formed between a surface selenium and an oxygen atom.…”

Vibrational frequencies of the impurity-centred oxygen tetrahedra in sillenites

“…The three dashed lines, which fit the n 3 values for 4+, 5+, and 6+ valence states, respectively, are guides for the eye, without any particular meaning of the fitting curve, but they show clearly the regular trend. The data related to Si ( 28 Si, 29 Si, and 30 Si) and S ( 32 S, 33 S, and 34 S) isotopes enrich the plot and fit perfectly the trend. If the large set of data, collected by Nakamoto for tetrahedral complexes embedded in hosts of different symmetries [1], is used for a similar plot, one finds a scattered behaviour instead of the smooth trend portrayed by dashed curves in Fig.…”

“…2. The SeO 4 groups are known to have poor solubility in solid matrices, as KCl and KBr [29], due also to the high Se vapour tension. The explanation why BTO can host more easily Se with respect to BSO and BGO can be found in a significant fraction of unoccupied tetrahedral sites in BTO [23].…”

Infrared Absorption and Local Symmetry of WO‐ and MoO Impurity Ions in KI and CsI Crystals

“…Similarly, for MOO;-a t vl(A1) = 896 em-l, w3(Bl) = 848 em-1, and v3(B2) = 821 em-l we obtain v3(A1) = 830 cm-l instead of the experimental value 877 em-]. I n calculations we use the usual value of the atomic weight of W because according to the relation (2) in [6] The agreement of experimental and calculated frequencies in the IR spectra of WOt-and MOO:-is, however, worse than that obtained a t the identification of similar I R spectra of other ITA, for instance, CrO2,-[4] and SO:- [l]. I n solution of the vibrational problem the matrix, composed using experimental frequencies of the components of v3, a t the transition to coordinates of symmetry CZv satisfies the condition of congruence to a considerably less degree in the case ofWO:-and MOO:-than in the case of SO:-and CrOi-.…”

“…The procedure is described in detail in [3, 61; in particular, to estimate the frequency of the component v3(A,) the relation (1) in [6] was used. The identification given corresponds to the best agreement of experimental and calculated values of v3(A,) and fully agrees with the previous distribution of components of the triplets v3 and v4 by the types of symmetry in the IR spectra of other ITA [l, 3,4, 61.…”