Your system may be 2-d (eg. surface), but you are doing the calculations in a three dimensional space. Therefore you get (2x3=) 6 phonon modes.
> I have confusion that in 2 dimension there should be only 4 optical phonons For a 2-d system with 2 atoms per unit cell, there will be (2x2=) 4 phonon modes, out of which 2 should be acoustic and 2 optical. Prasenjit. and corresponding 4 no. of raman > tensor matrices, but i am getting 6 tensors matrices. > Please help me.. > Thanks, > Arun > -- > PhD Student > JNCASR, Bangalore-560064 > India > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > -- PRASENJIT GHOSH, POST-DOC, ROOM NO: 265, MAIN BUILDING, CM SECTION, ICTP, STRADA COSTERIA 11, TRIESTE, 34104, ITALY PHONE: +39 040 2240 369 (O) +39 3807528672 (M) -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20081010/e8e6028c/attachment.htm
