JEDRSKA KVADRUPOLNA RESONANCA ¹⁷O

Osnovno stanje jedra ¹⁷O ima spin 5/2 in je zato šestkrat degenerirano. Sklopitev električnega kvadrupolnega momenta jedra z lokalnim nehomogenim električnim poljem delno odpravi degeneracijo. Dobimo tri dvakrat degenerirane energijske nivoje. V primeru, ko je gradient električnega polja osno simetričen in je asimetrijski parameter h enak nič, so lastna stanja kvadrupolnega hamiltoniana |±m>, pri čemer je m magnetno kvantno število, kvantizacijska os pa ima smer osi gradienta električnega polja. Energijske nivoje označimo kot »5/2«, »3/2« in »1/2«. Enake oznake energijskih nivojev obdržimo tudi, ko h ≠ 0. Frekvence prehoda med energijskimi nivoji imenujemo kvadrupolne resonančne frekvence. Označimo jih kot n_5/2-1/2 > n_5/2-3/2 ³ n_3/2-1/2.

Naravna koncentracija izotopa ¹⁷O je 0.037%, zato pogosto merimo kvadrupolne resonančne frekvence, ki so večinoma nižje od 5 MHz, z visoko občutljivimi metodami dvojne resonance ¹H-¹⁷O.

V primeru, ko je razdalja med jedrom kisika in najbližjim jedrom vodika majhna, opazimo dipolno strukturo kvadrupolnih resonančnih črt ¹⁷O, iz katere lahko določimo razdaljo med jedroma, orientacijo veznice O-H v lastnem sistemu gradienta električnega polja in znak kvadrupolne sklopitvene konstante.

Kratka teorija jedrske kvadrupolne resonance:

J. Seliger, Nuclear quadrupole resonance: theory, Poglavje v knjigi »Encyclopedia of Spectroscopy and Spectrometry«, Ed. J. C. Lindon, G. E. Tranter and J. L. Holmes, Academic Press, San Diego etc., 2000, p. 1672-1680

Objavljena dela:

1. R. Blinc, J. Seliger, R. Osredkar, T. Prelesnik, Double resonance study of the ¹⁷O

quadrupole coupling in paraelectric and ferroelectric KH₂PO₄, Chem. Phys.

Letters 23, 486-488 (1973)

2. R. Blinc, J. Seliger, R. Osredkar,M. Mali, ¹⁷O quadrupole resonance study of the

ferroelectric phase transition in KH2PO4, Phys. Letters 47A, 131-132 (1974)

3. J. Seliger, V. Žagar, R. Blinc, ¹⁷O NQR study of the ferroelectric phase transition

in PbHPO₄, Phys. Letters A 93, 149-151 (1983)

4. J. Seliger, V. Žagar, R. Blinc, Oxygen-17 NQR study of the phase transition in the

squaric acid, J. Magn. Reson. 58, 359-369 (1984)

5. J. Seliger, V. Žagar, R. Blinc, ¹⁷O NQR study of the pseudo-one-dimensional

ferroelectric phase transition in CsH₂PO₄, J. Chem. Phys. 81, 3247-3249 (1984)

6. J. Seliger, V. Žagar, R. Blinc, A. Novak, ¹⁷O and ³⁹K quadrupole resonance study

of the ferroelastic phase transition in KH₃(SeO₃)₂, J. Chem. Phys. 84, 5857-5861

(1986)

7. J. Seliger, V. Žagar, R. Blinc, A. Novak, S. Rodin, ¹⁷O and ¹⁴N quadrupole

coupling and the mechanism of the ferroelectric transition in diglycine nitrate,

Ferroelectrics Letters 6, 93-102 (1986)

8. S. V. Rodin, J. Seliger, R. Blinc, V. Žagar, JKR ¹⁴N i ¹⁷O v kristalle diglicinnitrata,

Fizika Tverdogo Tela, 29, 1871-1873 (1987)

9. J. Seliger, V. Žagar, R. Blinc, V. H. Schmidt, ¹⁷O NQR study of the antiferroelectric

phase transition in TlH₂PO₄, J. Chem. Phys. 88, 3260-3262 (1988)

10. J. Seliger, V. Žagar, R. Blinc, ¹H-¹⁷O nuclear quadrupole double resonance study

of hydrogen bonds in (CH₃COO)₂KH and (CH₃COO)₂NaH, Chem. Phys. Letters

164, 405-408 (1989)

11. J. Seliger, V. Žagar, R. Blinc, P. K. Kadaba, D. Fiat, ¹H-¹⁷O nuclear quadrupole

double resonance in DL-proline, Z. Naturforsch. 45a, 733-735 (1990)

12. J. Seliger, V. Žagar, R. Blinc, V. H. Schmidt, ⁸⁵Rb, ⁸⁷Rb, and ¹⁷O nuclear-

quadrupole resonance study of Rb(H_1-xD_x)₂PO₄, Phys. Rev. B 42, 3881-3886

(1990)

13. J. Seliger, V. Žagar, R. Blinc, E. Hadjoudis, F. Milia, ¹H-¹⁴N and ¹H-¹⁷O nuclear

quadrupole resonance in thermochromic N-5-chlorosalicylideneaniline,

Chem. Phys. 142, 237-244 (1990)

14. D. Abramič, J. Seliger, V. Žagar, R. Blinc, Nuclear quadrupole double resonance

in AHSO₄ (A=K, Rb, Cs, Tl, NH₄), J. Phys.: Condens. Matter 5, 3373-3380 (1993)

15. J. Seliger, V. Žagar, R. Blinc ,¹⁷O NQR study of glass order in

Rb_0.5(NH₄)_0.5H₂PO₄, Phys. Rev. B 52, 12519-12521 (1995)

16. J. Seliger, V. Žagar, ¹H-¹⁷O nuclear-quadrupole double-resonance study of

random fields in K_0.5(NH₄)_0.5H₂PO₄, J. Phys.: Condensed Matter 8, 1521-1525

(1996)

17. J. Seliger, ¹⁷O nuclear quadrupole coupling in C-O-H…O=C hydrogen bonds

Chem. Phys. 231, 81-86 (1998)

18. J. Seliger, V. Žagar, ¹⁷O NQR study of proton disorder in solid benzoic acid,

4-hydroxybenzoic acid and 4-nitrobenzoic acid, Chem. Phys. 234, 223-230

(1998)

19. M. Torkar, V. Žagar, J. Seliger, ¹H-¹⁷O nuclear-quadrupole double-

resonance study of hydrogen disorder in 2-nitrobenzoic acid, J. Magn. Reson.,

144, 13-19 (2000)

20. J. Seliger, A. Zidanšek, V. Žagar, R. Blinc, F. Milia, ¹⁷O and ²³Na nuclear

quadrupole double resonance of sodium formate and sodium acetate, Appl.

Magn. Reson. 26, 427 (2004)

21. J. Seliger, V. Žagar, R. Blinc, F. Milia, Temperature dependence of 17O and
 14N NQR frequencies in commercial TNT, Applied Magnetic Resonance 29, 
 541-548 (2005)

22. J. Seliger, V. Žagar, Sensitivity of nuclear-quadrupole double-resonance

detection of half-integer spin nuclei, J. Magn. Reson. 194, 175-181 (2008)

doi: 10.1016/j.jmr.2008.06.021

23. J. Seliger, V. Žagar, ¹H-¹⁷O nuclear quadrupole double resonance in

phenylphosphinic acid and phenylphosphonic acid. ¹⁷O quadrupole coupling in

P = O and P-O-H bonds, Magn. Reson. Chem. 46, 969-973 (2008)

doi: 10.1002/mrc.2296

24. J. Seliger, V. Žagar, Measurement of dipolar structure of ¹⁷O nuclear

quadrupole resonance lines by three-frequency irradiation, J. Magn. Reson.

203, 220-225 (2010) doi:10.1016/j.jmr.2009.12.022 

25. J. Latosińska, M. Latosińska, M. Tomczak, J. Seliger, V. Žagar, 
 Supramolecular synthon pattern in solid clioquinol and cloxiquine (APIs of
 antibacterial, antifungal, antiaging and antituberculosis drugs) studied by 35Cl
 NQR, 1H-17O and 1H-14N NQDR and DFT/QTAIM, J. Mol. Model. 
 doi: 10.1007/s00894-010-0876-4

26. J. Seliger, J. Plavec, P. Šket, V. Žagar, R. Blinc, ¹⁷O NQR and ¹³C NMR

study of hydrogen-bonded organic ferroelectric croconic acid, Phys. Status

 Solidi B 248, 2091-2096 (2011), doi: 10.1002/pssb.201046649

27. J. Seliger, Nuclear quadrupole resonance study of hydrogen bonded solid

materials, Acta Chim. Slov. 58, 471-477 (2011)

28. J. Seliger, V. Žagar, Phonon driven proton transfer in 3,5-pyridine

dicarboxylic acid studied by ²H, ¹⁴N and ¹⁷O NQR, J. Phys. Chem. A 115,

11652-11654 (2011) DOI: 10.1021/jp206897v

29. J. N. Latosińska, M. Latosińska, M. A. Tomczak, J. Seliger, V. Žagar,

J. K. Maurin, Conformations and intermolecular interactions pattern in solid

chloroxylenol and triclosan (API of anti-infective agents and drugs). A ³⁵Cl

NQR, ¹H-¹⁷O NQDR, X-ray and DFT/QTAIM study, Magn. Reson. Chem. 50,

89 – 105 (2012) DOI: 10.1002/mrc.2799.

30. J. Seliger, V. Žagar, Unusual electron charge density in carboxylic acid. 
 17O quadrupole coupling in cis-cyclobutane-1,2-dicarboxylic acid, 
 J. Phys. Chem. A 116, 7139-7146 (2012) DOI: 10.1021/jp301802v

31. J. Seliger, V. Žagar, Hydrogen Bonds in Cocrystals and Salts of 2-Amino-4,6-

Dimethylpyrimidine and Carboxylic Acids Studied by NQR, J. Phys. Chem. B

117, 6946-6956 (2013) DOI: 10.1021/jp403617e

32. J. Stare, A. Gradišek, J. Seliger Nuclear quadrupole resonance supported by

periodic quantum calculations: a sensitive tool for precise structural

characterization of short hydrogen bonds, Phys. Chem. Chem. Phys., 22,

27681-27689 (2020) DOI: 10.1039/d0cp04710d