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A misfit layer oxide Tl0.41(Sr0.9O)1.12CoO2 has been synthesized, and its structural model established by ED and HREM. The cell parameters of the two subsystems have been refined from XRPD data. The subsystem S1 (a = 4.9498(5) Å, b 1 = 5.0222(6) Å, c = 11.656(1) Å, β = 97.755(7)°) characterizes the strontium-deficient rock-salt layers [(Sr0.9□0.1)O]∞, whereas the subsystem S2 (a = 4.9498(5) Å, b 2 = 2.807(2) Å, c = 11.656(1) Å, β = 97.755(7)°) corresponds to the octahedral [CoO2]∞ layers that exhibit the CdI2 structure. The thallium atoms are located between the two kinds of layers, with a distorded tetrahedral coordination, ensuring the cohesion of the structure.

Mossbauer spectroscopy of damage induced by energetic Ar, Kr, and Xe ions in the giga-electronvolt range in two ferrimagnetic oxides, Y3Fe5012 and BaFe120l9, is presented. The enhancement of the paramagnetic phase observed after an irradiation with high-energy deposition (Xe and Kr ions) compared to low-energy deposition (Ar ions) supports a damage mechanism based on the electronic stopping power. Threshold energy-deposition values close to 17 and 25 MeVcm mg ' have thus been determined for Y3Fe50» and BaFelzOl9, respectively. Furthermore, drastic changes in the bulk orientation of the hyperfine magnetic field Hf have been observed in yttrium iron garnet: The Hf distribution is isotropic for Ar irradiations and anisotropic for Xe irradiations, while two types of Hf distributions are observed for Kr irradiations, depending on the values of the deposited energy compared to that of the threshold energy. Comparison with latent-track models is performed.

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