| Title |
Optimization of parameters for semiempirical methods V: Modification of NDDO approximations and application to 70 elements
|
|---|---|
| Published in |
Journal of Molecular Modeling, September 2007
|
| DOI | 10.1007/s00894-007-0233-4 |
| Pubmed ID | |
| Authors |
James J. P. Stewart |
| Abstract |
Several modifications that have been made to the NDDO core-core interaction term and to the method of parameter optimization are described. These changes have resulted in a more complete parameter optimization, called PM6, which has, in turn, allowed 70 elements to be parameterized. The average unsigned error (AUE) between calculated and reference heats of formation for 4,492 species was 8.0 kcal mol(-1). For the subset of 1,373 compounds involving only the elements H, C, N, O, F, P, S, Cl, and Br, the PM6 AUE was 4.4 kcal mol(-1). The equivalent AUE for other methods were: RM1: 5.0, B3LYP 6-31G*: 5.2, PM5: 5.7, PM3: 6.3, HF 6-31G*: 7.4, and AM1: 10.0 kcal mol(-1). Several long-standing faults in AM1 and PM3 have been corrected and significant improvements have been made in the prediction of geometries. |
Mendeley readers
The data shown below were compiled from readership statistics for 1,476 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 16 | 1% |
| Germany | 13 | <1% |
| Brazil | 13 | <1% |
| Italy | 4 | <1% |
| Japan | 3 | <1% |
| Canada | 3 | <1% |
| France | 3 | <1% |
| United Kingdom | 3 | <1% |
| Czechia | 3 | <1% |
| Other | 27 | 2% |
| Unknown | 1388 | 94% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Ph. D. Student | 326 | 22% |
| Researcher | 209 | 14% |
| Student > Master | 179 | 12% |
| Student > Bachelor | 162 | 11% |
| Professor > Associate Professor | 84 | 6% |
| Other | 255 | 17% |
| Unknown | 261 | 18% |
| Readers by discipline | Count | As % |
|---|---|---|
| Chemistry | 773 | 52% |
| Physics and Astronomy | 71 | 5% |
| Agricultural and Biological Sciences | 56 | 4% |
| Biochemistry, Genetics and Molecular Biology | 51 | 3% |
| Materials Science | 48 | 3% |
| Other | 159 | 11% |
| Unknown | 318 | 22% |
Attention Score in Context
This research output has an Altmetric Attention Score of 12. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 16 June 2022.
All research outputs
#2,671,019
of 22,684,168 outputs
Outputs from Journal of Molecular Modeling
#22
of 807 outputs
Outputs of similar age
#6,542
of 69,866 outputs
Outputs of similar age from Journal of Molecular Modeling
#2
of 6 outputs
Altmetric has tracked 22,684,168 research outputs across all sources so far. Compared to these this one has done well and is in the 88th percentile: it's in the top 25% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 807 research outputs from this source. They receive a mean Attention Score of 2.7. This one has done particularly well, scoring higher than 97% of its peers.
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We're also able to compare this research output to 6 others from the same source and published within six weeks on either side of this one. This one has scored higher than 4 of them.