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<body class='hmmessage'><div dir='ltr'>To whom it may concern<br><br>My name is Leong. Currently I am using Quantum Espresso to calculate proton diffusion through graphene. <br><br>1. I would like to know how to generate a proton in the scf input file?<br>2. Besides, if there is a proton in the system (with positive 1 charge), is that it is compulsory to create jellium background to neutral the system since the system is periodic?<br><br>Wish to receive your reply soon.<br><br><br>Thank you.<br><br><br>Best regards<br>Leong<br> </div></body>
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