Hi All,<br><br>In my simulation, the NO3- is used, in which the three N-O bond length is constraints. And a planar triangular structure is used. <br>I used the type "1" of [ constraints ] to constraint the bond length. Because I only find angle constraints which is used on H-involved angles,
<br>I used the type "2" of [ constraints ] to constraint the length between Os. (The distance is calculated from the triangular structure). After the Energy Minimization, all the bong length become very long (much bigger than the box length). Who knows how to solve it?
<br><br>Sincerely yours,<br>Baofu Qiao, PhD<br><br>