1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
On the number of significant mode-mode anharmonic couplings in vibrational calculations: Correlation-corrected vibrational self-consistent field treatment of di-, tri-, and tetrapeptides
Rent:
Rent this article for
USD
10.1063/1.2909558
/content/aip/journal/jcp/128/16/10.1063/1.2909558
http://aip.metastore.ingenta.com/content/aip/journal/jcp/128/16/10.1063/1.2909558

Figures

Image of FIG. 1.
FIG. 1.

Histogram of the absolute coupling potential of all the normal-mode pairs for glycine and ValGlyVal. This histogram shows that most of the normal-mode pairs have a very low coupling potential, and only a few normal-mode pairs have a high coupling potential.

Image of FIG. 2.
FIG. 2.

An illustration of the main concept of the PIC rank. This graph includes four pairs of normal modes. The first two pairs [(A) and (B)] have a high PIC rank, while the other two pairs [(C) and (D)] have a low PIC rank. The percentiles are calculated over all the normal-mode pairs of glycine. (Pair A) is an example of two normal modes that have a very high coupling potential and, indeed, have a very high PIC rank. The PIC rank of this pair is in the 100th percentile (the highest value) and the coupling potential is , which is in the 98.5th percentile. (Pair B) is another example of two normal modes that have a very high coupling potential and, indeed, have a very high PIC rank. The PIC rank of this pair is in the 98th percentile and the coupling potential is , which is in the 99.5th percentile. (Pair C) is an example of two normal modes that have a very weak coupling potential and, indeed, have a low PIC rank. The PIC rank of this pair is in the 0.3th percentile (the lowest value) and the coupling potential is , which is in the 1st percentile. (Pair D) is another example of two normal modes that have a weak coupling potential and, indeed, have a low PIC rank. The PIC rank of this pair is in the 7th percentile and the coupling potential is , which is in the 2nd percentile.

Image of FIG. 3.
FIG. 3.

Profile of the mean errors according to the different subject type. The regression lines are as follows: For the glycines (glycine and diglycine to tetraglycine), with ; for the valines (only 2 values valine and divaline), with ; and for the alanines (alanine, dialanine, and trialanine), with .

Image of FIG. 4.
FIG. 4.

The distribution of the absolute difference between the PIC CC-VSCF and the full CC-VSCF. The distribution line is taken from exponential distribution with , which is the mean value of the errors of ValGlyVal.

Image of FIG. 5.
FIG. 5.

A plot which describe a comparison between the observed values and the expected normal values. If the observed variable matches the normal distribution, the points cluster around a straight line.

Image of FIG. 6.
FIG. 6.

The average error of the CC-VSCF while using only the normal-mode pairs with the highest PIC rank.

Image of FIG. 7.
FIG. 7.

The average error of the CC-VSCF with (1) PIC , (2) normal-mode with the strongest coupling, and (3) normal-mode with the strongest coupling. In the first case, the regression line is with , in the second case, with , and in the third case, with .

Image of FIG. 8.
FIG. 8.

The CPU time of the PIC version (the CPU time of CC-VSCF method when calculating only the normal-mode pairs with the highest PIC rank) and the CPU time of the full version (the CPU time of CC-VSCF method when calculating all the normal-mode pairs). The linear line is for the original version with , and for the improved version the line is with

Tables

Generic image for table
Table I.

Spearman’s rank correlation coefficient for several peptides. The correlation is between the PIC rank and the coupled potential for the group of the entire normal-mode pairs for each subject. All the correlations were found to be significant with -value smaller than 0.0005.

Generic image for table
Table II.

The accuracy of CC-VSCF method when using only the normal-mode pairs with the highest PIC rank.

Generic image for table
Table III.

The accuracy of CC-VSCF method when using only the normal-mode pairs with the highest coupled potential (optimal choose).

Generic image for table
Table IV.

The percentage of the normal-modes pairs with highest potential among the normal-mode pairs with the highest PIC rank. Let be a group that contained the normal-mode pairs with the highest coupling potential among the normal-modes pairs. . Let be a group that contains the normal-modes pairs, chosen, using the PIC criteria. .

Generic image for table
Table V.

The CPU time of the PIC version (the CPU time of CC-VSCF method when calculating only the normal-mode pairs with the highest PIC rank) and the CPU time of the full version (the CPU time of CC-VSCF method when calculating all the normal-mode pairs).

Loading

Article metrics loading...

/content/aip/journal/jcp/128/16/10.1063/1.2909558
2008-04-30
2014-04-21
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: On the number of significant mode-mode anharmonic couplings in vibrational calculations: Correlation-corrected vibrational self-consistent field treatment of di-, tri-, and tetrapeptides
http://aip.metastore.ingenta.com/content/aip/journal/jcp/128/16/10.1063/1.2909558
10.1063/1.2909558
SEARCH_EXPAND_ITEM