Evolution of ferromagnetic stability with magnetic impurity and vacancies in Cr-doped CaZn2As2 system

•The Ca(Zn, Cr)2As2 systems with and without vacancy were magnetic.•Eight different Ca8(Zn14Cr2)As16 configurations with different distance of Cr-Cr pairs preferred FM states.•Cr atoms provided the magnetic moment forming the Cr-As-Cr chain with the p-d hybridization coupling.•The ferromagnetic state of p-type Ca8(Zn14Cr2)As16 with a VCa or VZn system was more stable, and the ferromagnetic stability of n-type Ca8(Zn14Cr2)As16 with VAs was reduced.