Bi2Se3未考虑vdw的错误

在没有考虑vdw作用之前，算Bi2Se3材料soc中出现的错误汇总VASP自旋轨道耦合计算错误汇总静态计算时，报错：VERYBADNEWS!Internal内部errorinsubroutine子程序IBZKPT:Reciprocal倒数的latticeandk-latticebelongtodifferentclassoflattices.Oftenresultsarestilluseful...48INCAR参数设置：对策：根据所用集群，修改INCAR中NPAR。将NPAR=4变成NPAR=1，已解决！错误：subspacematrix类错误报错：静态和能带计算中出现警告：WARNING:Sub-Space-Matrixisnothermitian共轭inDAV结构优化出现错误：WARNING:Sub-Space-MatrixisnothermitianinDAV4-4.681828688433112E-002对策：通过将默认AMIX=0.4，修改成AMIX=0.2（或0.3），问题得以解决。以下是类似的错误：WARNING:Sub-Space-Matrixisnothermitianinrmm-3.00000000000000RMM:22-0.167633596124E+02-0.57393E+00-0.44312E-0113260.221E+00BRMIX:veryseriousproblemstheoldandthenewchargedensitydifferoldchargedensity:28.00003new28.060930.111E+00错误：WARNING:Sub-Space-Matrixisnothermitianinrmm-42.5000000000000ERRORFEXCP:suppliedExchange-correletiontableistoosmall,maximalindex:4794错误：结构优化Bi2Te3时，log文件：WARNINGinEDDIAG:subspacematrixisnothermitian1-0.199E+01RMM:2000.179366581305E+01-0.10588E-01-0.14220E+007180.261E-01BRMIX:veryseriousproblemstheoldandthenewchargedensitydifferoldchargedensity:56.00230new124.7039466F=0.17936658E+01E0=0.18295246E+01dE=0.557217E-02curvature:0.00expectdE=0.000E+00dEforcontlinesearch0.000E+00ZBRENT:fatalerrorinbracketingpleasererunwithsmallerEDIFF,orcopyCONTCARtoPOSCARandcontinue但是，将CONTCAR拷贝成POSCAR，接着算静态没有报错，这样算出来的结果有问题吗？对策1：用这个CONTCAR拷贝成POSCAR重新做一次结构优化，看是否达到优化精度！对策2：用这个CONTCAR拷贝成POSCAR，并且修改EDIFF（目前参数EDIFF=1E-6）,默认为10-4错误：WARNING:Sub-Space-MatrixisnothermitianinDAV1-7.626640664998020E-003网上参考解决方案：对策1：减小POTIM:IBRION=0，标准分子动力学模拟。通过POTIM控制步长。POTIM：当IBRION=1,2或3时，是力的一个缩放常数（相当于确定原子每步移动的大小），默认值为0.5。对策2：改IBRION=1，采用准牛顿算法来优化原子的位置。原IBRION=2，采用共轭梯度算法来优化原子的位置对策3：修改ISMEAR对策4：换成CG弛豫（共轭梯度算法）IBRION=2(决定结构优化过程中，原子如何移动或弛豫)IBRION=2离子是否运动，1不运动但做NSW外循环。0动力学模拟，1准牛顿法离子弛豫2CG法离子弛豫，3采用衰减二阶运动方程离子弛豫，INCARrelax中设置IBRION=2，未解决！对策5：用的CG算符，出现的错误是CG算符不能算，在INCAR中加上IALG=Fast（电子优化采用blockedDavidson方法[IALGO=38:IALG=Normal]和RMM-DIIS算法[IALGO=48:IALG=Very_Fast]混合）试一试IALG=Fast(两种方法混用)IALG=Very_Fast(等价于IALGO=48)IALG=Normal（等价于IALGO=38）INCAR中加上IALG=Fast已解决！（1QL、2QL已解决，3QL以上未解决）VASPFORUM:theerrorisduetoaLAPCKcall(ZHEGV):ZHEGVcomputesalltheeigenvalues本征值,andoptionally随意地,theeigenvectorsofacomplexgeneralizedHermitian-definiteeigenproblem.theremaybeseveralreasonsforthaterror:1)theRMM-DIISdiagonalisationalgorithmisnotstableforyourspecificsetupofthecalculation.--useALGO=Normal(blockedDavidson)orALGO=Fast(5stepsblockedDavidson,RMM-DIIS)用ALGO=NormalIALGO=48或者ALGO=Fast2)a)maybeyourinputgeometrywasnotreasonable(erroroccursattheveryfirstionicstep,pleasehavealookforthegeometrydataofyourruninOUTCAR)orb)thelastionicrelaxationstepleadtoanunreasonablegeometry(comparetheinputandoutputgeometriesofthelastionicrelaxationstepsinXDATCAR).Inthatcase(2b)itcanbehelpfulto--switchtoadifferentrelaxationalgorithm(IBRION-tag)--reducethestepsizeofthefirststepbysettingPOTIMsmallerthanthedefaultvalue改变IBRION，减少步长POTIM3)TheinstallationoftheLAPACKonyourmachinewasnotdoneproperly:usetheLAPACKwhichisdeliveredwiththecode(vasp.4.lib/lapack_double.o)4)IftheerrorpersistalthoughyouswitchedtotheDavidsonalgorithm:onsomearchitectures(especiallySGI)someLAPACKroutinesarenotworkingproperly.However,itispossibletoavoidtheusageoftheZHEGVsubroutinebycommentingtheline#defineUSE_ZHEEVXindavidson.F,subrot.F,andwavpre_noio.FandrecompilingVASP.关于Mixing方法的调试：针对这类错误：DAV:13-0.242323773333E+030.98155E+02-0.87140E+01488320.949E+01BRMIX:veryseriousproblemstheoldandthenewchargedensitydifferoldchargedensity:252.00012new252.299790.809E+01WARNING:Sub-Space-MatrixisnothermitianinDAV90.133520549894753.....解决办法只需调整AMIX,BMIX的值，把他们设置小一些。Mixing方法：IMIX=typeofmixing混合、混频，AMIX=linearmixingparameter，AMIN=minimalmixingparameter,BMIX=cutoffwavevectorforKerkermixingscheme,AMIX_MAG=linearmixingparameterformagnetization,BMIX_MAG=cutoffwavevectorforKerkermixingschemeformag,WC=weightfactorforeachstepinBroydenmixingscheme,INIMIX=typeofinitialforeachstepinBroydenmixingscheme,MIXPRE=typeofpreconditioninginBroydenmixingscheme,MAXMIX=maximumnumberstepsstoredinBroydenmixer.一般采用其默认值，除非在电子迭代难以收敛的情况，才手动设置AMIX和BMIX等参数值。】对策：grepAMIXOUTCARAMIX=0.40;BMIX=1.00AMIX_MAG=1.60;BMIX_MAG=1.00initialmixingisaKerkertypemixingwithAMIX=0.4000andBMIX=1.0000设置：初始值收敛值结果AMIX=0.0100；BMIX=0.0001AMIX=0.01;BMIX=0.00计算无误AMIX=0.1000；BMIX=0.0010AMIX=0.10;BMIX=0.00计算无误AMIX=0.20;BMIX=0.01AMIX=0.20;BMIX=0.01计算无误AMIX=0.2、BMIX=0.001AMIX=0.2、BMIX=0.001计算无误AMIX=0.3、BMIX=0.1AMIX=0.3、BMIX=0.1计算无误AMIX=0.4AMIX=0.40;BMIX=1.00静态log:WARNINGinEDDRMM:calltoZHEGVfailed,returncode=63**,能带一样AMIX=0.02AMIX=0.02;BMIX=1.00计算无误AMIX=0.1AMIX=0.10;BMIX=1.00静态log:WARNINGinEDDRMM:calltoZHEGVfailed,returncode=63**,能带一样AMIX=0.3AMIX=0.30;BMIX=1.00静态log:WARNINGinEDDRMM:calltoZHEGVfailed,returncode=63**,能带一样BMIX=0.0001AMIX=0.40;BMIX=0.00计算无误以上参数设置，得到的能带图都一样，如下图:综上：设置AMIX=0.2（或0.3）,BMIX默认（省事，等于1.0），可以保证计算过程无误。还需进一步调整其他参数，算出正确的能带。警告：算1QL弛豫、静态、能带时，都有这个提示：ADVICETOTHISUSERRUNNING'VASP/VAMP'(HEARYOURMASTER'SVOICE...):Youhavea(moreorless)'smallsupercell'andforsmallercellsitisrecommendedtousethereciprocal-spaceprojectionscheme!Therealspaceoptimiz