Can O2 Play an Important Role

Mossbauer spectra of BaFe2As2 at T=90K and different atmospheric pressures 1 mTorr (a), 35 mTorr (b), 40 mTorr (c), 160 mTorr (d), and 750 mTorr (e) [23], 

26 SOME MOSSBAUERSTUDIES OF Fe-As-BASED HIGH-TEMPERATURE SUPERCONDUCTORS 

The authors gratefully acknowledge the generous support from NSF DMR-MRI 0922735. 

Kasinathan, A. Ormeci, K. Koch, U. Burkhardt, W. Schnelle, A. Leithe-Jasper, H. Rosner, New J. Phys. 2009, II, 025023. 

Khasanov, S.C. Bhargava, J.G. Stevens, J. Jiang, J.D. Weiss, E.E. Hellstrom, A. Nath,J. Phys Condens. Matter 2011, 23, 202201. I I. P. Bonville, F. Rullier-Albenque, D. Colson, A. Forget, Eur. Phys. Lett. 2010, 89, 67008. 

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