Singularities of Møller-Plesset series: example "o3"
Molecule F-. Basis cc-pVTZ-(f). Structure ""
Content
- Definition of quadratic approximants
- Approximant [0, 0, 0]
- Approximant [1, 0, 0]
- Approximant [1, 1, 0]
- Approximant [1, 1, 1]
- Approximant [2, 1, 1]
- Approximant [2, 2, 1]
- Approximant [2, 2, 2]
- Approximant [3, 2, 2]
- Approximant [3, 3, 2]
- Approximant [3, 3, 3]
- Approximant [4, 3, 3]
- Approximant [4, 4, 3]
| Examples | o1 | o2 | o3 | o4 | o5 | o6 | o7 | o8 | o9 |
| Molecule | Ne | Ne | F- | HF | H2O | CH2 | CH2 | C2 | N2 |
| Basis | cc-pVDZ | cc-pVTZ-(f) | cc-pVTZ-(f) | cc-pVTZ-(f/d) | cc-pVDZ(+) | aug-cc-pVDZ | cc-pVTZ-(f/d) | cc-pVDZ(+) | cc-pVDZ |
Quadratic approximants
[n1, n2, n3] approximant is defined
as a solution of the quadratic equation
A(z)f2 + B(z)f + C(z) = 0
with polynomial coefficients A(z),
B(z) and
C(z) of degree
n3, n2 and n1 respectively.
Square-root singularities are determined as zeroes of the discriminant
D(z) = B2(z) - 4A(z)C(z).
The weight c of the singularity zc is defined so that
f ~ c(1 - z/zc)1/2 at z -> zc.
The weight is calculated by formula
c = 1/2[-z(D/A2)']1/2
where r. h. s. of the above equation is evaluated at z = zc.
Table 1. Singularities with their weights for the quadratic approximant [0, 0, 0] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
![Singularities of quadratic [0, 0, 0] approximant](singsq1.gif?508579) |
Top of the page
Table 2. Singularities with their weights for the quadratic approximant [1, 0, 0] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
![Singularities of quadratic [1, 0, 0] approximant](singsq2.gif?152895) |
Top of the page
Table 3. Singularities with their weights for the quadratic approximant [1, 1, 0] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -0.4351 | 0.0373 |
![Singularities of quadratic [1, 1, 0] approximant](singsq3.gif?160963) |
2 | -0.6483 | 0.0456 i |
Top of the page
Table 4. Singularities with their weights for the quadratic approximant [1, 1, 1] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -1.8087 | 0.671 |
![Singularities of quadratic [1, 1, 1] approximant](singsq4.gif?984631) |
2 | 4.9355 | 45.9 |
Top of the page
Table 5. Singularities with their weights for the quadratic approximant [2, 1, 1] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -1.5549 | 0.322 |
![Singularities of quadratic [2, 1, 1] approximant](singsq5.gif?851316) |
2 | 2.5855 + 3.2621 i | 0.743 + 0.225 i |
3 | 2.5855 - 3.2621 i | 0.743 - 0.225 i |
Top of the page
Table 6. Singularities with their weights for the quadratic approximant [2, 2, 1] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -2.2237 | 5.05 |
![Singularities of quadratic [2, 2, 1] approximant](singsq6.gif?521971) |
2 | 2.8386 | 0.96 |
3 | -4.0505 | 1.48 i |
4 | 90.2541 | 4.32 i |
Top of the page
Table 7. Singularities with their weights for the quadratic approximant [2, 2, 2] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -2.012 | 1.64 |
![Singularities of quadratic [2, 2, 2] approximant](singsq7.gif?593932) |
2 | 2.6096 | 0.765 |
3 | 7.26 | 1.28 i |
4 | -9.5994 | 0.781 i |
Top of the page
Table 8. Singularities with their weights for the quadratic approximant [3, 2, 2] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -1.9851 | 1.17 |
![Singularities of quadratic [3, 2, 2] approximant](singsq8.gif?171837) |
2 | 2.0338 + 0.1298 i | 0.0498 - 0.0726 i |
3 | 2.0338 - 0.1298 i | 0.0498 + 0.0726 i |
4 | 2.3362 | 0.103 |
5 | -5.1074 | 1.84 i |
Top of the page
Table 9. Singularities with their weights for the quadratic approximant [3, 3, 2] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -2.0947 | 3.28 |
![Singularities of quadratic [3, 3, 2] approximant](singsq9.gif?2723) |
2 | 2.4434 | 0.46 |
3 | -4.4385 + 8.8953 i | 0.503 - 0.368 i |
4 | -4.4385 - 8.8953 i | 0.503 + 0.368 i |
5 | 9.9435 | 2.13 i |
6 | -12.3749 | 0.547 i |
Top of the page
Table 10. Singularities with their weights for the quadratic approximant [3, 3, 3] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -2.1747 | 13.9 |
![Singularities of quadratic [3, 3, 3] approximant](singsq10.gif?467447) |
2 | 2.2677 | 0.219 |
3 | 0.9268 + 3.5737 i | 0.177 - 0.017 i |
4 | 0.9268 - 3.5737 i | 0.177 + 0.017 i |
5 | -0.0148 + 3.9484 i | 0.0311 - 0.184 i |
6 | -0.0148 - 3.9484 i | 0.0311 + 0.184 i |
Top of the page
Table 11. Singularities with their weights for the quadratic approximant [4, 3, 3] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | -0.4332 + 0.e-4 i | 0.000615 + 0.000615 i |
![Singularities of quadratic [4, 3, 3] approximant](singsq11.gif?203551) |
2 | -0.4332 - 0.e-4 i | 0.000615 - 0.000615 i |
3 | -2.0783 | 3.28 |
4 | 2.2047 + 0.5186 i | 0.0805 - 0.118 i |
5 | 2.2047 - 0.5186 i | 0.0805 + 0.118 i |
6 | 2.5886 | 0.131 |
7 | -6.9014 | 1.16 i |
Top of the page
Table 12. Singularities with their weights for the quadratic approximant [4, 4, 3] The most stable singularity is highlighted. |
| No. | zc | c | Location in the complex plane |
1 | 0.4224 | 0.000224 |
![Singularities of quadratic [4, 4, 3] approximant](singsq12.gif?698567) |
2 | 0.4224 | 0.000224 i |
3 | -0.8618 + 0.0015 i | 0.00374 + 0.00372 i |
4 | -0.8618 - 0.0015 i | 0.00374 - 0.00372 i |
5 | -2.0847 | 5.48 |
6 | 2.2643 | 0.186 |
7 | -5.8915 | 2.05 i |
8 | 327.0342 | 20.8 i |
Top of the page
| Examples | o1 | o2 | o3 | o4 | o5 | o6 | o7 | o8 | o9 |
| Molecule | Ne | Ne | F- | HF | H2O | CH2 | CH2 | C2 | N2 |
| Basis | cc-pVDZ | cc-pVTZ-(f) | cc-pVTZ-(f) | cc-pVTZ-(f/d) | cc-pVDZ(+) | aug-cc-pVDZ | cc-pVTZ-(f/d) | cc-pVDZ(+) | cc-pVDZ |
Designed by A. Sergeev.