Abstract
Neutron profile refinement analysis conducted on Bi 1.6Pb 0.4Ca 1Sr 2Cu 2O y (Space Group Amaa) points to Pb-ions substituting at Bi-sites as Pb 4+. A comparative study of air-annealed and vacuum-annealed samples of Bi 1.6Pb 0.4Ca 1Sr 2Cu 2O y indicates a slight reduction in the cell parameters upon annealing in vacuum in line with the observation of a reduction in oxygen-content per formula unit ( y) from 8.72 for the air-annealed sample to 8.39 for the vacuum-annealed one. We propose that the rather high value of y(=8.72) for the air-annealed sample is due to the formation of dimerised oxygen-species in the bismuth layer. The significant tilting of Cu-O 5 pyramids observed for air-annealed Bi 1.6Pb 0.4Ca 1Sr 2Cu 2O y is nearly eliminated upon vacuum-annealing treatment which is suggestive of a reduction in the hole-density as confirmed by a marginal drop in T c ( R=0) from 93 to 89 K after vacuum-annealing treatment.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
