关于DOSCAR原子态密度相加不等于总态密度的问题很多人也许都碰到，造成这种不一致的原因在VASP的手册里面提到了，主要可能是两个原因；
1.RWIGS设置的原因
这是由于态密度局限在RWIGS半径内，而无法等于整个体积造成，所以手册特意提及：
Please keep in mind that results are qualitative — i.e. there is no unambiguous way to determine the location of an electron. With the current implementation, it is for instance hardly possible to determine charge transfer. What can be derived from the partial DOS is the typical character of a peak in a DOS. Quantitative results can be obtained only by carefull comparison with a reference system (e.g. bulk versus surface).
2.LORBIT设置的原因
当设置有LORBIT时，由于本身势不带有分波和角动量投影态密度，这样的区别还会大一些，特别是设置成>=10时，INCAR中的RWIGS将被忽略，而使用自带的PAW方法进行投影。
The wave function character is calculated, either by projecting the wavefunctions onto spherical harmonics that are non zero within spheres of a radius RWIGS around each ion (LORIT=1, 2), or using a quick projection scheme relying that works only for the PAW method (LORBIT=10,11,12, see below). If the LORBIT flag is not equal zero, the site and l-projected density of states is also calculated.
在网上也有人发现过这样的问题，当然这无法完全解决。但是如果要得到的原子态密度和更接近于总态密度，从手册以及网上一些分析这样设置INCAR比较好。
1.不计算分波及角动量投影态密度，使用较大（适当）的RWIGS,即
NPAR=1；RWIGS=.....；LORBIT=.FALSE.
2.计算分波及角动量投影态密度，使用较大（适当）的RWIGS，而不是用PAW方法（LORBIT>=10）,即
NPAR=1; RWIGS=.....; LORBIT=0-5
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