<html><body><div style="font-family: arial,helvetica,sans-serif; font-size: 12pt; color: #000000"><div>Hi.<br></div><div><br>I am not an expert of VCA, but if you google it as, "virtual crystal approximation quantum espresso" for example,  I presume you can find some clues at least.<br></div><div><br></div><div>Hope this helps.<br></div><div><br></div><div>Federico.<br></div><div><br></div><div><span name="x"></span><table class="mceItemTable" xmlns="urn:zimbraAccount"><tbody><tr><td><img alt="Université Paris-Sud" src="https://zimbra.u-psud.fr/public/z_logo_signature.png" style="border: 0pt none;width:120px;height:107px;background:url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAHgAAABrBAMAAABOCFvUAAAAHlBMVEX8//t9goSEv0OutbhxdngNXILX6sOr1H/Y3uBema/9PDtXAAAF7UlEQVR4Xu3Wv4+byhYH8GOcC6RjBIVLi4JpseBJbkdL4TJStFK2G1FAiyigxfJeya+7UhQpf+77nhkwttc31/FK771iT2wGD/PhDPODDd0fH+GLd+BlegaqfowGIMPHN4ctjv72kGVDhi8dsvRwxBm+2xN123gKDZwTiWWR4rATAy1Xm6IIclWsllERbLJCFNuiUCcbz0ETVgHj15T2QT4Qbch/WgQoU1I4pVO0s5UnHD4xRvs8tZjEfvUWe/Ec6xNe5QPwcodfGzwvMqM32wmfntk5w3rG+wDYD/2Q8MzDZiF2tFepxUWxe9vrmGa8CIEp4twpuvsacudX1902SvYc3YTVcuULwXATWIxzomV4C0tNc+Tbw9NyRbkC2Ecpfh/xzGLwj4cp8/F4htcXy0dFAdwCGOcD7iICQYunvYjS3OBCKAa+xQ2dx2FL/kB+hgMvt+PxOBxRIOg40JF8PkN8JmoNfiQ+D1Q+jv8y85w8hP2vZmlLeiieB/PQ3QzsCE1nNsVUgeL8+o9v5F2N90YgMuYLu/WWXBFuwYonIt9cN/hPpC4vdQ4bFSEUzyxjxRUKpwp4X8Aqg/94fiFqL/RGFAUa8O7F0WBUKAHIWET4ZfHy+fknuUbrCYembyu0EzgCF0h6iCKDlwpVU/x4fv5Obj9rxtAixHeF8xHzMge2PxDjQ7Omet4eAPa4VMFeDBOGsjiYsf+MeLE6ucSfomERpdcY34vU0IPResbodi7IV8GEFxZTFIWXqaFT1skJHzAuGF98R+zn0WDwXkXhcNL/nnQbyxFnWRQFJuurMPiQCaXIYD9XRXjZcWhe5dpgXhWKFoIjShlvcBIYDB2h8mK6EN+ojBuDmaW0FyYCxihDshhaiN2MfasHN17bzFk2oLQ4tHhLFo+Lna41UicG2zoRHhEbwXgfrc4wvWLwzoL1C3nn2K5DLBNgX6nhDC8u8WfbbzljrC/bLgXGPVYXmYmuU/9FvcW2QWrvsQPmQRoYm1cn5u0W7macj4MinhjTfpyqRYGIdrewZmX7FtmC8uLAeKnUjNXwFn8xKsvsYK8sXgieOJ65lHjeMkR6aX1YZP69OI7xrwcwZmiMd+PhHfhlBAd+Pwb2FfDJDO72n/E3a/2I39MT5jd2VKx+jedeLxRnO2EBLtTwSzwP116wohFHOB6ECH6JX37OfzHoCqMz4d/gr1gy2yPRjIdrzNviNv5yVYfdd41pE92JFwLgCu9R3IUpEmp7hRd34yV0+iimQyHCRzG0itKHMUY8eHDAEL7azdjO/f2YgFVwer37QtBvZfbNkrRqI1a38ct1hw5YrpsogNseN2LnZ9uNEukt/NZSzttfDLRXKAuMOiKkW/g77A3Mrf3cqFe2A90ZGWJLBJ2FKM1/zR+Lj/iIZfZg0H89PkK/w7bxbe3oubyKfgJe4iU3sXcHdhrSXqzrto913zZe27Sd1ybcIRnjAnApieq2i227xosltd2Eqa3XZRXX67ZLnK7uei9p3aTVssIFYFk2ZK+jXSedTnpdf8I9rWuStG6pd7RTlV7j1I2jE5JVQk6V4BZ8PekpKanHB230iKuOkpp6d8R9b7DHuO+AZd8QXz/Dvc3srb0EbsQJcOMCV2vO3JMmlC5Z3LprxhopXDIRx00ZNxbHIG4sGccxcBmvCQMQj5nRjtPG0rRh7HbkVuRSRbqtiZNoFzeu8ZtQSaTRwl4n266q0Ab4Mlq6Pzx9hWv6Pwj3gUve2yfA5N7YMW6n3+CSrgO4obdR951pL/njtDyruk08mXja0TXvDNQDA8SJu8a/uHGl5J3SNl1fcX5Zu7LUWO0kayq1JxvGJbU1VoU22O1awpotqwRNG+BOdxVjb03u2uMakhWVhMk3GMhN6sZgwj5oPd1Wcmyqyav1JcZeLfU5lr3N7MlWO/B9N2G79iBPWHtri5vS4jWRwQ7fVBJazHjaGNS2ZojitnESYFfGugbiehxwN1S4CTkyucauthvD5QL35i7ZDWAqaKwgLjRf56b/4/gPHroRZdvxtdsAAAAASUVORK5CYII=" data-mce-src="https://zimbra.u-psud.fr/public/z_logo_signature.png" data-mce-style="border: 0pt none; width: 120px; height: 107px; background: url(data:image/png;"></td><td valign="top"><div><span style="font-size: 10pt" data-mce-style="font-size: 10pt;"><b>Federico IORI</b></span></div><div><span style="font-size: 10pt" data-mce-style="font-size: 10pt;">Marie Curie Fellow<br>Laboratoire de Physique des Solides<br>Bâtiment 510 - Rue André Rivière<br>91400 Orsay</span></div></td></tr></tbody></table><div><br></div><span name="x"></span><br></div><hr id="zwchr"><div style="color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;" data-mce-style="color: #000; font-weight: normal; font-style: normal; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-size: 12pt;"><b>De: </b>"Abdullah N. Albarakati" <anbarakati@uqu.edu.sa><br><b>Para: </b>"PWSCF Forum ‎[pw_forum@pwscf.org]‎" <pw_forum@pwscf.org><br><b>Enviados: </b>Jueves, 8 de Diciembre 2016 16:13:06<br><b>Asunto: </b>[Pw_forum] virtual crystal approximation<br><div><br></div><style id="owaParaStyle">P {margin-top:0;margin-bottom:0;}</style><div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;" data-mce-style="direction: ltr; font-family: Tahoma; color: #000000; font-size: 10pt;"><br> Dear QE experts,<br> <br> Can we use virtual crystal approximation method with Quantum Espresso codes (pw.x)?<br> <br> If yes, How?<br> <br> Thank you in advance<br> <br> Dr. Abdullah<br> Umm Al-Qura University<br> Saudi Arabia<br></div><br><hr><span data-mce-style="color: gray; font-family: Arial; font-size: xx-small;" style="color: gray; font-family: Arial; font-size: xx-small;" color="Gray" size="1"><br> This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify Email System Administrator (e_admin@uqu.edu.sa ) . Please note that any views or opinions presented in this email are solely those of the author and do not necessarily represent those of the Umm Al-Qura University. Finally, the recipient should check this email and any attachments for the presence of viruses. The Information Technology and Technical Support Center of Umm Al-Qura University accepts no liability for any damage caused by any virus transmitted by this email.<br> </span><br>_______________________________________________<br>Pw_forum mailing list<br>Pw_forum@pwscf.org<br>http://pwscf.org/mailman/listinfo/pw_forum</div><div><br></div></div></body></html>