George E. Boyd

Raman Spectra of Molten NaBF4 to 606°C and 8% NaF‐92% to 503°C

The Raman spectra of molten NaBF4 samples have been measured to 606°C, and spectra of samples of the eutectic mixture of 8 mole % NaF in NaBF4 were recorded to 503° using 4880‐A radiation from an argon‐ion laser for excitation. The BF4− ion appeared to retain its tetrahedral symmetry under all the conditions studied in this investigation. The frequency of the ν1(a1) mode of BF4− decreased with increasing melt temperature, and weak, asymmetric features on the bands from the ν2(e) and ν4(f2) modes were observed in molten NaBF4 and in the melts with 8 mole % NaF. The interpretation of the Raman spectra of molten NaBF4 does not require postulating the existence of a quasilattice structure or phonons in the molten state.

Ionic Interactions in Crystals: Infrared and Raman Spectra of Powdered Ca(NO3)2, Sr(NO3)2, Ba(NO3)2, and Pb(NO3)2

Infrared and Raman spectra have been recorded for room‐temperature phase powdered samples of Ca(NO3)2, Sr(NO3)2, Ba(NO3)2, and Pb(NO3)2. The spectra are interpreted in terms of a factor group analysis. Considerable multiplet band structure is reported for the first time.

Infrared Emission Spectra of Molten Salts

Infrared emission spectra of molten alkali metal nitrates and chlorates were recorded over the frequency interval from 50 to 3000 cm−1 employing a Fourier transform spectrometer. Emission spectra of molten mixtures of NaNO3 and NaClO3 also were measured, and the ν3 mode of NO−3 ion was observed with solutions containing about 0.1 mole % NaNO3. Far infrared spectra of the melts revealed a broad band which progressively shifted to a lower frequency as the mass of the cation increased. The emission spectrum of each salt at a given temperature was recorded in fewer than 2 min and was of comparable or of better quality than previously reported infrared spectra.

Raman spectra of O−2 and O−3 ions in alkali-metal superoxides and ozonides

Abstract Raman spectra of polycrystalline NaO2, KO2, RbO2, CsO2, KO3, and CsO3 were measured from 75 to 300°K. Solid-solid phase transition effeccts were noted in spectra of the sodium, potassium, and rubidium superoxides, but none was detected with CsO2. External mode frequencies were observed in the 211−200, 146−122, and 89−62 cm−1 regions in the low temperature spectra of KO2 and RbO2. Spectra of KO3 and CsO3 exhibited a single band at ca. 1010 cm−1 which was assigned to the symmetric stretching mode of the O−3 ion.

Infrared and Raman Spectra of Polycrystalline NaBF4

The infrared and Raman spectra of polycrystalline NaBF4 and the Raman spectrum of an aqueous solution of NaBF4 were measured at 298°K in the region above 200 cm−1. With the exception of ν3, all of the predicted correlation field components arising from multiplet splitting of the BF4− vibrations were identified in the polycrystalline spectra.

Raman spectral studies of molten lithium nitrate-lithium perchlorate mixtures

Abstract The Raman spectra of molten LiNO 3 , LiClO 4 , and mixtures of the two salts are reported. All bands appear to arise from highly localized vibrational modes. The spectral features of molten LiNO 3 can be accounted for by the hypothesis that two non-equivalent environments are available to the nitrate ion.

Vibrational spectra of crystalline, molten and aqueous potassium dichromate

Abstract Raman and infrared spectra of crystalline potassium dichromate were measured at −196°C, and Raman spectra were recorded at successive temperatures from 25°C to above the solid-solid phase transition at 269°C. Raman spectra of molten K2Cr2O7 at 435°C and of a saturated aqueous solution of K2Cr2O7 at 25° also were measured. Two-site and correlation field splitting of the internal modes of dichromate ion in the low temperature solid phase are discussed, and the assignment of the Raman active external modes in the crystal is considered using a cell model. The results from a calculation of the 21 normal modes of dichromate ion are presented to support the proposed frequency assignments.

Raman spectra of vitreous, polycrystalline, and molten BeF2 to 630°C and the infrared spectrum of vitreous BeF2 at 25°C

Abstract Raman spectra of vitreous, polycrystalline, and molten BeF 2 were measured over a temperature range from 25 to 630°C, and the infrared spectrum of vitreous BeF 2 was measured at 25°C. The vibrational spectrum of vitreous BeF 2 is consistent with a model based on the structure of β-quartz. The Raman spectra of the high-temperature modification of crystalline BeF 2 and of molten BeF 2 contained single bands at 343 and 288 cm −1 , respectively.

Vibrational spectra of molten and aqueous NaClO3 and KClO3

Abstract Raman spectra of molten NaClO3 and KClO3 and of aqueous solutions of these salts were measured over the frequency interval from 50 to 1200 cm−1|. Infrared emission spectra of the molten chlorates and of chlorate-nitrate mixtures were recorded, and absorption spectra of aqueous sodium and potassium chlorate also were determined. The ν3(e) and ν4(e) modes of ClO−3 were split in the molten salt and aqueous solution spectra, and a single, weak band was observed between ca. 80 and 200 cm− in the Raman spectra of molten NaClO3 and KClO3.

The Nature of the Selective Binding of Ions by Polyelectrolyte Gels: Volume and Entropy Change Criteria

The volume, ΔV 0, and entropy, ΔS 0, changes which accompany the selective binding of ions in ion exchange reactions at 25° between aqueous electrolyte mixtures and polyelectrolyte gels are considered in a discussion of the range of applicability of the Katchalsky and Rice-Harris theories. Experimental methods for the estimation of ΔV 0 are reviewed, and dilatometer measurements with soft and hard cationic and anionic gels are reported. Apparent molal volume determinations with aqueous model compound and linear polyeletrolyte-analog solutions also were conducted to elucidate the nature of the hydration of polyelectrolyte gels.