INDO stands for Intermediate Neglect of Differential Overlap. It is a semi-empirical quantum chemistry method that is a development of the complete neglect of differential overlap

CNDO/2

CNDO is the abbreviation for Complete Neglect of Differential Overlap. Although CNDO is based on quantum chemistry, it is more specifically one of the first semi-empirical quantum chemistry methods. It uses two approximations:...

 (CNDO/2) method introduced by John Pople

John Pople

Sir John Anthony Pople, KBE, FRS, was a Nobel-Prize winning theoretical chemist. Born in Burnham-on-Sea, Somerset, England, he attended Bristol Grammar School. He won a scholarship to Trinity College, Cambridge in 1943. He received his B. A. in 1946. Between 1945 and 1947 he worked at the Bristol...

. Like CNDO/2 it uses zero-differential overlap

Zero-differential overlap

Zero differential overlap is an approximation that is used to ignore certain integrals, usually two-electron repulsion integrals, in semi-empirical quantum chemistry methods quantum chemistry molecular orbital methods....

 for the two-electron integrals but not for integrals that are over orbitals centered on the same atom.

The method is now rarely used in its original form but it is the basis for several other methods, such as MINDO

MINDO

MINDO, or Modified Intermediate Neglect of Differential Overlap is a semi-empirical method for the quantum calculation of molecular electronic structure in computational chemistry. It is based on the Intermediate Neglect of Differential Overlap method of John Pople. It was developed by the group...

, ZINDO

ZINDO

ZINDO is a semi-empirical quantum chemistry method used in computational chemistry. It is a development of the INDO method. It stands for Zerner's Intermediate Neglect of Differential Overlap, as it was developed by Michael Zerner...

 and SINDO

SINDO

SINDO, or actually SINDO1, is one of many semi-empirical quantum chemistry methods. It stands for symmetric orthogonalised INDO and was developed by K. Jug and coworkers. Like MINDO, it is a development of the INDO method. The main development is the inclusion of d orbitals for atoms of the...

.