### Abstract

Two closely related energy partitioning schemes, in which the total energy is presented as a sum of atomic and diatomic contributions by using the "atomic decomposition of identity", are compared on the example of N, N-dimethylformamide, a simple but chemically rich molecule. Both schemes account for different intramolecular interactions, for instance they identify the weak C-H⋯O intramolecular interactions, but give completely different numbers. (The energy decomposition scheme based on the virial theorem is also considered.) The comparison of the two schemes resulted in a dilemma which is especially striking when these schemes are applied for molecules distorted from their equilibrium structures: one either gets numbers which are "on the chemical scale" and have quite appealing values at the equilibrium molecular geometries, but exhibiting a counter-intuitive distance dependence (the two-center energy components increase in absolute value with the increase of the interatomic distances) - or numbers with too large absolute values but "correct" distance behaviour. The problem is connected with the quick decay of the diatomic kinetic energy components.

Original language | English |
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Pages (from-to) | 439-450 |

Number of pages | 12 |

Journal | Faraday Discussions |

Volume | 135 |

DOIs | |

Publication status | Published - 2007 |

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### ASJC Scopus subject areas

- Physical and Theoretical Chemistry

### Cite this

*Faraday Discussions*,

*135*, 439-450. https://doi.org/10.1039/b609463e

**Energy partitioning schemes : A dilemma.** / Mayer, I.

Research output: Contribution to journal › Article

*Faraday Discussions*, vol. 135, pp. 439-450. https://doi.org/10.1039/b609463e

}

TY - JOUR

T1 - Energy partitioning schemes

T2 - A dilemma

AU - Mayer, I.

PY - 2007

Y1 - 2007

N2 - Two closely related energy partitioning schemes, in which the total energy is presented as a sum of atomic and diatomic contributions by using the "atomic decomposition of identity", are compared on the example of N, N-dimethylformamide, a simple but chemically rich molecule. Both schemes account for different intramolecular interactions, for instance they identify the weak C-H⋯O intramolecular interactions, but give completely different numbers. (The energy decomposition scheme based on the virial theorem is also considered.) The comparison of the two schemes resulted in a dilemma which is especially striking when these schemes are applied for molecules distorted from their equilibrium structures: one either gets numbers which are "on the chemical scale" and have quite appealing values at the equilibrium molecular geometries, but exhibiting a counter-intuitive distance dependence (the two-center energy components increase in absolute value with the increase of the interatomic distances) - or numbers with too large absolute values but "correct" distance behaviour. The problem is connected with the quick decay of the diatomic kinetic energy components.

AB - Two closely related energy partitioning schemes, in which the total energy is presented as a sum of atomic and diatomic contributions by using the "atomic decomposition of identity", are compared on the example of N, N-dimethylformamide, a simple but chemically rich molecule. Both schemes account for different intramolecular interactions, for instance they identify the weak C-H⋯O intramolecular interactions, but give completely different numbers. (The energy decomposition scheme based on the virial theorem is also considered.) The comparison of the two schemes resulted in a dilemma which is especially striking when these schemes are applied for molecules distorted from their equilibrium structures: one either gets numbers which are "on the chemical scale" and have quite appealing values at the equilibrium molecular geometries, but exhibiting a counter-intuitive distance dependence (the two-center energy components increase in absolute value with the increase of the interatomic distances) - or numbers with too large absolute values but "correct" distance behaviour. The problem is connected with the quick decay of the diatomic kinetic energy components.

UR - http://www.scopus.com/inward/record.url?scp=33845880870&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33845880870&partnerID=8YFLogxK

U2 - 10.1039/b609463e

DO - 10.1039/b609463e

M3 - Article

AN - SCOPUS:33845880870

VL - 135

SP - 439

EP - 450

JO - Faraday Discussions

JF - Faraday Discussions

SN - 1364-5498

ER -