我们用Pd金属作为例子。Pd金属的实验上的晶格常数为3.89A。在这里，我们用VASP计算它的晶格常数。首先将Pd所对应的POTCAR文件拷贝到目录下。然后准备好INCAR和KPOINTS文件。POSCAR文件我们将通过一个tcsh的script来产生。KPOINTS文件可以如下：MonkhorstPack0MonkhorstPack111111000INCAR文件可以如下：SYSTEM=PdbulkcalculationStartparameterforthisrun:PREC=AccurateISTART=0job:0-new1-cont2-samecutICHARG=2charge:1-file2-atom10-constISPIN=1spinpolarizedcalculation?ElectronicRelaxation1EDIFF=0.1E-03stopping-criterionforELMLREAL=.FALSE.real-spaceprojectionIonicrelaxationEDIFFG=0.1E-02stopping-criterionforIOMNSW=0numberofstepsforIOMIBRION=2ionicrelax:0-MD1-quasi-New2-CGISIF=2stressandrelaxationPOTIM=0.10time-stepforionic-motionTEIN=0.0initialtemperatureTEBEG=0.0;TEEND=0.0temperatureduringrunDOSrelatedvalues:ISMEAR=0;SIGMA=0.05gaussiansmearElectronicrelaxation2(details)WriteflagsLWAVE=FwriteWAVECARLCHARG=FwriteCHGCAR产生POSCAR和计算晶格常数的工作可以用以下的PBSscript来完成。#!/bin/tcsh#PBS-S/bin/sh#PBS-lnodes=4:athlon:ppn=2#PBS-lcput=384:00:00#PBS-mae#PBS-ooutput#PBS-eerror.log#setparametersetEXEC='vasp'setSRC='/usr/common/executable'#changeworkingdirectorycd$PBS_O_WORKDIR#copyfreshexecutablefromdepositorycp-f$SRC/$EXEC.#executempiprogramforeacha(3.33.43.53.63.7)echo"a=$a"cat>POSCAR<cubicdiamond$a0.50.50.00.00.50.50.50.00.52direct0.00.00.00.250.250.25!mpiexec-nostdin./$EXECsetE=`tail-2OSZICAR`echo$a$E>>SUMMARYend#removeexecutablerm-f$EXEC如果不用不需要用PBSscript，则更加简单，如下即可。将其命名为lattice。#!/bin/tcshforeacha(3.53.63.73.83.94.04.14.2)echo"a=$a"cat>POSCAR<fcclattice$a0.50.50.00.00.50.50.50.00.51cartesian0.00.00.0!./vaspsetE=`tail-1OSZICAR`echo$a$E>>SUMMARYend用chmod+xlattice，将其改为可执行文件。然后在命令行里键入./lattice即可。以下是用USPP-LDA运行完后的SUMMARY文件。每个计算用时13秒。（在USPP中Pd的截断能量是198.955）3.51F=-.52384500E+01E0=-.52371846E+01dE=-.253072E-023.61F=-.58695670E+01E0=-.58683951E+01dE=-.234381E-023.71F=-.62322232E+01E0=-.62311104E+01dE=-.222547E-023.81F=-.63932936E+01E0=-.63921078E+01dE=-.237151E-023.91F=-.64072233E+01E0=-.64058584E+0