<html><body><div style="font-family: times new roman, new york, times, serif; font-size: 12pt; color: #000000"><div data-marker="__QUOTED_TEXT__"><div style="font-family: times new roman, new york, times, serif; font-size: 12pt; color: #000000"><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">Dear users,</div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><br></div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">I am currently trying to perform phonon calculations on LaTe3, and one keypoint in order to have good results is a very well relaxed structure. For this purpose I use a force threshold of 1d-05 (see input file attached).</div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><br></div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">However, I find that it is very difficult to achieve this threshold (and it becomes harder when increasing the density of k-points). For a k-grid of 12 x 2 x 12 I try to relax the structure and eventually the bfgs algorithm gets stuck</div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">into the same three configurations. <span style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;" data-mce-style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;">My strategy so far has been to reintroduce the best structure from the output into the input file and relaunch it but I can not achieve forces less than 6d-05.</span><div style="clear: both;" data-mce-style="clear: both;"><br data-mce-bogus="1"></div></div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">I ask you for some advice in order to achieve my threshold in case you have some experience with this kind of materials.</div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><br></div><div style="color: #000000; font-family: 'times new roman', 'new york', times, serif; font-size: 16px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #fdfdfd; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><div><span style="font-size: 18pt;"><strong>Alejandro Lasso Castillo</strong></span><br><em>Erasmus Mundus Joint Master Student</em><br><em>Quantum Science and Technologies (QUARMEN)</em></div></div></div><br></div></div></body></html>