Related Experiment Video
Updated: Mar 29, 2026

Generating Strictly Controlled Stimuli for Figure Recognition Experiments
Published on: March 18, 2019
A Fast Implementation of Perfect Pairing and Imperfect Pairing Using the Resolution of the Identity Approximation
Alex Sodt1, Greg J O Beran1, Yousung Jung1
1Department of Chemistry, University of California, Berkeley, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-1460.
Abstract:
We present an efficient implementation of the perfect pairing and imperfect pairing coupled-cluster methods, as well as their nuclear gradients, using the resolution of the identity approximation to calculate two-electron integrals. The perfect pairing and imperfect pairing equations may be solved rapidly, making integral evaluation the bottleneck step. The method's efficiency is demonstrated for a series of linear alkanes, for which we show significant speed-ups (of approximately a factor of 10) with negligible error. We also apply the imperfect pairing method to a model of a recently synthesized stable singlet biradicaloid based on a planar Ge-N-Ge-N ring, confirming its biradical character, which appears to be remarkably high.
Related Concept Videos
Sign Test for Matched Pairs
To conduct the sign test, we first calculate the differences in...
Synthetic Disvision of Polynomials
Equivalent Couples
Two couples are considered to be equivalent if they produce the same rotational effect on a rigid body. In other words, the two couples have the same magnitude and act in the same direction, causing the same angular displacement or acceleration in the body.
For instance, consider two couples lying in the plane of the page, with one having a pair of equal...
Linearization and Approximation
Wilcoxon Signed-Ranks Test for Matched Pairs
Application of Linearization and Approximation

