Alkaline earth doped

Among the alkali metals, Li, Na, K, Rb, and Cs and their alloys have been used as exohedral dopants for Cgo [25, 26], with one electron typically transferred per alkali metal dopant. Although the metal atom diffusion rates appear to be considerably lower, some success has also been achieved with the intercalation of alkaline earth dopants, such as Ca, Sr, and Ba [27, 28, 29], where two electrons per metal atom M are transferred to the Cgo molecules for low concentrations of metal atoms, and less than two electrons per alkaline earth ion for high metal atom concentrations. Since the alkaline earth ions are smaller than the corresponding alkali metals in the same row of the periodic table, the crystal structures formed with alkaline earth doping are often different from those for the alkali metal dopants. Except for the alkali metal and alkaline earth intercalation compounds, few intercalation compounds have been investigated for their physical properties. 

Ianculescu A, Braileanu A, Pasuk I, and Zaharescu M. Phase formation study of alkaline earth-doped lanthanum chromites. J. Therm. Anal. Calorimetry 2001 66 501-507. 

Tanasescu S, Orasanu A, Berger D, Jitaru I, and Shoonman J. Electrical conductivity and thermodynamic properties of some alkaline earth-doped lanthanum chromites. Int. J. Thermophysics 2005 26 543-557. 

The resistivity behavior of La2Cu04, and several other substituted La2Cu04 derivatives, were studied (121) in the USSR. In many samples, the alkaline-earth ions were substituted for the Las+ ion. Their results indicated metallic behavior for La2Cu04 and all the measured alkaline-earth derivatives, but semiconductive behavior for the other Ln2Cu04 parent compounds and their alkaline-earth derivatives. Selected resistivity data for alkaline-earth doped La2Cu04 derivatives are presented in Figure 23. 

Baskaran, S., Lewinsohn, C.A., Chou, Y.S., Qian, M., Stevenson, J.W., and Armstrong, T.R., Mechanical properties of alkaline earth-doped lanthanum gallate. Journal of Materials Science, 1999, 34, 3913-3922. 

Fig. 10.12 Transition curves for superconductivity in the alkali-and alkaline-earth-doped Fullerene crystals. The real part x of the ac susceptibility, normalised for T 0 K to -1 (i.e. the value for ideal diamagnetism), is plotted against the temperature. After [10].

Chen, D.Q., Yu, Y.L., Huang, F., Wang, Y.S., 2011c. Phase transition from hexagonal LnFs (Ln = La, Ce, Pr) to cubic Lno.8Mo.2F2.8 (M = Ca, Sr, Ba) nanocrystals with enhanced upconversion induced by alkaline-earth doping. Chem. Coimnun. 47, 2601-2603. 

Phosphors of the type A2 jB P207 (where A and B are alkaline earths) doped with Eu +Mn + have been reported [97]. Transition metal phosphonates can also exhibit photoluminescence. A range of colours can be obtained from compounds of type Zn, jMn/PhP03)H20 [96]. 

Maximum lattice ionic conductivities in the range of 0.04-0.06 S cm at 800 °C have been reported with alkaline-earth doping, with... 

Saito, S. and Oshiyama, A., Electronic structure of alkali and alkaline earth doped solid... 

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