X-Git-Url: https://hackdaworld.org/gitweb/?p=lectures%2Flatex.git;a=blobdiff_plain;f=posic%2Fthesis%2Fd_tersoff.tex;h=b031be2f58ecd016152de51b4e26e136c23450aa;hp=66abaed4244eb2f648ab13ae766c57ab2b0f09cd;hb=17d5c879c418790a154098e51c524eca183c4d98;hpb=5ddcac8e0e73d86f761b20d37efcd66ce41c7f08 diff --git a/posic/thesis/d_tersoff.tex b/posic/thesis/d_tersoff.tex index 66abaed..b031be2 100644 --- a/posic/thesis/d_tersoff.tex +++ b/posic/thesis/d_tersoff.tex @@ -32,13 +32,13 @@ f_C(r_{ij}) = \left\{ 0, & r_{ij} > S_{ij} \end{array} \right. \end{equation} -with $\theta_{ijk}$ being the bond angle between bonds $ij$ and $ik$ as shown in Figure \ref{img:tersoff_angle}.\\ +with $\theta_{ijk}$ being the bond angle between bonds $ij$ and $ik$ as shown in Figure~\ref{img:tersoff_angle}.\\ \\ For a three body potential, if $V_{ij}$ is not equal to $V_{ji}$, the derivative is of the form \begin{equation} \nabla_{{\bf r}_i} E = \frac{1}{2} \big[ \sum_j ( \nabla_{{\bf r}_i} V_{ij} + \nabla_{{\bf r}_i} V_{ji} ) + \sum_k \sum_j \nabla_{{\bf r}_i} V_{jk} \big] \textrm{ .} \end{equation} -In the following all the necessary derivatives to calculate $\nabla_{{\bf r}_i} E$ are written down. +In the following, all the necessary derivatives to calculate $\nabla_{{\bf r}_i} E$ are written down. \section[Derivative of $V_{ij}$ with respect to ${r}_i$]{\boldmath Derivative of $V_{ij}$ with respect to ${\bf r}_i$} @@ -138,7 +138,7 @@ are calculated and added in subsequent loops. b_{ij} \nabla_{{\bf r}_j} f_A(r_{ij}) + f_A(r_{ij}) \nabla_{{\bf r}_j} b_{ij} \big] \end{eqnarray} -Using the equality $\nabla_{{\bf r}_i} r_{ij}=-\nabla_{{\bf r}_j} r_{ij}$ +Using the equality $\nabla_{{\bf r}_i} r_{ij}=-\nabla_{{\bf r}_j} r_{ij}$, the following relations are valid: \begin{eqnarray} \nabla_{{\bf r}_j} f_R(r_{ij}) &=& - \nabla_{{\bf r}_i} f_R(r_{ij}) \\