Characterization of synthetic hedenbergite (CaFeSi 2 O 6 )?petedunnite (CaZnSi 2 O 6 ) solid solution series by X-ray powder diffraction and 57 Fe M�ssbauer spectroscopy

A comparison of the clinopyroxene compounds CaZnSi2O6and CaZnGe2O6

“…Our lattice parameters of CaZnSi 2 O 6 are similar to those given in the literature (Essene & Peacor, 1987;Ohashi et al, 1996;Huber et al, 2004). The latter authors have determined the lattice parameters of petedunnite, but no additional structure information.…”

The (Na,Li)FeGe2O6 clinopyroxene-type series: a temperature-dependent single-crystal X-ray diffraction and 57Fe Mössbauer spectroscopic study

“…Only small changes with T and phase transition occur for the Li bonds to the O1 oxygen atoms, while in the Li-O2 bond lengths-again-there are some larger variations at T close to the phase transition with the Li-O2B iv bond becoming distinctly extended between 180 K and 200 K. On average, the 〈Li-O〉 increases with T, decreases at the phase transition, and then again increases (Fig. 12b) (Heuer et al 2005), Ca-deficient cpx = data from Benna et al (1988), Tribaudino and Nestola (2002), Mantovani et al (2014), Li 1−x Na x FeSi 2 O 6 series from Redhammer and Roth (2002), CaMg 1−x Fe x Si 2 O 6 series from Raudsepp et al (1990), LiM 3+ Si 2 O 6 data from Redhammer and Roth (2004a) data show that there is no abrupt break in most of the structural parameters but a gradual approach of the P2 1 /c values toward the ones of the C2/c structure. This takes place over a temperature range of ~20 K. For the 〈Fe-O〉, a behavior similar to the 〈Li-O〉 bonds is observed, and the average F-O bonds increase with T and become somewhat shorter at the phase transition.…”

Usage of P–V–L bond theory in studying the structural/property regulation of microwave dielectric ceramics: a review

“…Clinopyroxene-type ABC 2 O 6 (A = Ca; B = Co, Mg, Zn, Fe; CvSi, Ge) materials are crystallized as a monoclinic structure with a C2/c space group. [96][97][98] Huber found out that the petedunnite CaZnSi 2 O 6 phase stabilizes at P > 0.8 GPa; otherwise, it decomposes into Zn 2 SiO 4 , Ca 2 ZnSi 2 O 7 and SiO 2 if the pressure is low and temperature exceeds 650 °C. 99 Distortions of the polyhedra were quantitatively analysed by Heuer in a CaBSi 2 O 6 system (B = Fe, Zn).…”

“…99 Distortions of the polyhedra were quantitatively analysed by Heuer in a CaBSi 2 O 6 system (B = Fe, Zn). 96 Recently, microwave dielectric properties of CaBSi 2 O 6 (B = Co, Mg) were reported: ε r = 6.04, Q × f = 12 457 GHz, and τ f = −18.91 ppm per °C for B = Co, 100 sintered at 1175 °C; and ε r = 7.46, Q × f = 59 638 GHz, and τ f = −46 ppm per °C for B = Mg, 101 sintered at 1290 °C. CaMgSi 2 O 6 ceramics are suitable candidates for electronic circuit packaging and microwave substrates as a result of their low ε r value and low dielectric loss.…”