IMPERFECTION OF SOLID & ATOM MOVEMENT

You may find the discussion about this topic in:

https://docs.google.com/file/d/0B3OOiHwWphGWcHdfLVdJTVN0Z1E/edit

Below (in Figure 1)  you can watch the mechanism of vacancies formation

Figure 1. The mechanism of vacancies formation due to doping of higher oxidation state ions into the crystallite structure. It can be seen in here that an Ag+ ion must be released then produce a vacancy in order to keep the nett charge of crystal in neutral

There are 3 mechanisms of ionic migration, i.e :
1. vacancy mechanism ( mekanisme kekosongan)
2. interstitial mechanism (mekanisme selitan)
3. the combination of vacancy and interstitial mechanism (mekanisme kekosongan dan selitan)

for better understanding on that mechanisms, please watch the animations below (Figure 2, Figure 3 and Figure 4).

Figure 2. The interstitial and vacancy mechanisms

Figure 3. The vacancy mechanism

Figure 4. The interstitial mechanism

*This blog was written by Fitria Rahmawati for Kuliah Elektrokimia Fasa Padatan
Fitria Rahmawati
Research Group of Solid State & Catalysis
Chemistry Department
Sebelas Maret University
Jl. Ir. Sutami 36 A Kentingan Surakarta 57126