ab initio

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ab initio

(ahb i-nish-ē-ō),
From the beginning.

ab initio

Latin, from the beginning; used in the working medical parlance to mean formulated without experimental data.
References in periodicals archive ?
07], which was developed by Hurly and Mehl (6) based on the best ab initio calculations available in 2007.
The ab initio method involves a more fundamental approach to solving the Schrodinger equation than does the semiempirical method, although there are some assumptions implicit in such calculations (16), The basic approximation of ab initio calculation is that the total wave function is a single Slater determinant and the resultant expression of the molecular orbitals is a linear combination of atomic orbital basis functions (LCAO): in other word, ab initio calculation can be initiated once a basis for the LCAO is chosen.
Finally, we wish to point out that the fact that the as-calculated ab initio multiplet (Fit A) requires adjustments, albeit small, of the individual lines' integrated intensities (via their widths) to achieve a near-perfect fit (Fit B) indicates that while our calculation captures the essentials of the spectrum, further effects, such as slightly less-than-full relaxation and/or final- and initial-state correlations, may need to be included in the ab initio calculations to achieve a good agreement with the measurements.
The three core courses are Quantum Chemistry and Methods of Computational Chemistry, which give the theoretical background, and Computational Chemistry Methods Laboratory, which gives a deeper analysis of the computational methods in use, such as molecular mechanics, semiempirical and ab initio calculations, and density functional theory.
1]), but with the cis conformer being the more stable form which is consistent with predictions from ab initio calculations at the highest level of calculations, Mp2/6-311 +G(2d,2p).
In addition, the potential energy surface is compared to recently reported Ab Initio calculations for [H.
From the ab initio calculations, atmospheric lifetimes were estimated to range from 0.
F] = 0) elcctric-quadrupolc transition at 282 nm due to external fields are calculated, based on a combination of measured atomic parameters and ab initio calculations.