Dear nic, After may friends here pointed out that the cutoff may be the reason for my small cell parameters. So I increase the cutoff to 30 Ry and try again. The results seems to be more satisfied. And I'll increase it to 40 Ry or more. I'll show my results later. Thank you for your advise. I'll check it later.
Vega Lew PH.D Candidate in Chemical Engineering State Key Laboratory of Materials-oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology, 210009, Nanjing, Jiangsu, China m _________________________________________________________________ Connect to the next generation of MSN Messenger? http://imagine-msn.com/messenger/launch80/default.aspx?locale=en-us&source=wlmailtagline -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20080704/a4bceba6/attachment.htm