Single crystal electron paramagnetic resonance spectra of CuII ions in Cu(tyrosine)2: A study of weak exchange interactions mediated by resonance assisted hydrogen bonds (RAHB)

Verónica Paredes-García, Ricardo C. Santana, Rosa Madrid, Bianca Baldo, Andrés Vega, Evgenia Spodine

Resultado de la investigación: Article

6 Citas (Scopus)

Resumen

EPR measurements have been performed on single crystals of [Cu(L-tyrosine)2]az at 33.8 GHz and at room temperature. The EPR spectra display partially resolved EPR lines for most orientations of the magnetic field in the ab plane, and only one resonance for orientations close to the crystal axes, while only a single line is observed along any direction in the ca and cb crystal planes. This behavior is a result of the selective collapse of the resonances corresponding to the four copper sites in the unit cell produced by the exchange interactions between the copper ions. The magnitudes of the exchange interactions between the copper ions were evaluated from the angular variation of the line width and the collapse of the EPR lines. The value |JAD/kB| = 0.8 K between neighboring copper atoms at 4.942 Å is assigned to a syn-anti equatorial-apical carboxylate bridge with a total bond length of 6.822 Å, while the small value |J AB/kB| = 0.004 K is assigned to a long bridge of 11 atoms with a total bond length of 19.186 Å, that includes one resonance assisted hydrogen bond (RAHB). This finding is discussed in terms of values obtained for similar paths in other model compounds and in proteins.

Idioma originalEnglish
Páginas (desde-hasta)75-81
Número de páginas7
PublicaciónJournal of Inorganic Biochemistry
Volumen114
DOI
EstadoPublished - 1 sep 2012

Huella dactilar

Exchange interactions
Electron Spin Resonance Spectroscopy
Paramagnetic resonance
Copper
Hydrogen
Hydrogen bonds
Single crystals
Ions
Bond length
Atoms
Crystals
Magnetic Fields
Crystal orientation
Linewidth
Tyrosine
Magnetic fields
Temperature
copper(II)-tyrosine complex
Proteins

ASJC Scopus subject areas

  • Biochemistry
  • Inorganic Chemistry

Citar esto

@article{f93ec15a715d4a6a8b9c6ef824c0833a,
title = "Single crystal electron paramagnetic resonance spectra of CuII ions in Cu(tyrosine)2: A study of weak exchange interactions mediated by resonance assisted hydrogen bonds (RAHB)",
abstract = "EPR measurements have been performed on single crystals of [Cu(L-tyrosine)2]az at 33.8 GHz and at room temperature. The EPR spectra display partially resolved EPR lines for most orientations of the magnetic field in the ab plane, and only one resonance for orientations close to the crystal axes, while only a single line is observed along any direction in the ca and cb crystal planes. This behavior is a result of the selective collapse of the resonances corresponding to the four copper sites in the unit cell produced by the exchange interactions between the copper ions. The magnitudes of the exchange interactions between the copper ions were evaluated from the angular variation of the line width and the collapse of the EPR lines. The value |JAD/kB| = 0.8 K between neighboring copper atoms at 4.942 {\AA} is assigned to a syn-anti equatorial-apical carboxylate bridge with a total bond length of 6.822 {\AA}, while the small value |J AB/kB| = 0.004 K is assigned to a long bridge of 11 atoms with a total bond length of 19.186 {\AA}, that includes one resonance assisted hydrogen bond (RAHB). This finding is discussed in terms of values obtained for similar paths in other model compounds and in proteins.",
keywords = "Biomolecules, Copper complexes, EPR spectroscopy, Exchange interaction, Model systems",
author = "Ver{\'o}nica Paredes-Garc{\'i}a and Santana, {Ricardo C.} and Rosa Madrid and Bianca Baldo and Andr{\'e}s Vega and Evgenia Spodine",
year = "2012",
month = "9",
day = "1",
doi = "10.1016/j.jinorgbio.2012.04.013",
language = "English",
volume = "114",
pages = "75--81",
journal = "Journal of Inorganic Biochemistry",
issn = "0162-0134",
publisher = "Elsevier Inc.",

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TY - JOUR

T1 - Single crystal electron paramagnetic resonance spectra of CuII ions in Cu(tyrosine)2

T2 - A study of weak exchange interactions mediated by resonance assisted hydrogen bonds (RAHB)

AU - Paredes-García, Verónica

AU - Santana, Ricardo C.

AU - Madrid, Rosa

AU - Baldo, Bianca

AU - Vega, Andrés

AU - Spodine, Evgenia

PY - 2012/9/1

Y1 - 2012/9/1

N2 - EPR measurements have been performed on single crystals of [Cu(L-tyrosine)2]az at 33.8 GHz and at room temperature. The EPR spectra display partially resolved EPR lines for most orientations of the magnetic field in the ab plane, and only one resonance for orientations close to the crystal axes, while only a single line is observed along any direction in the ca and cb crystal planes. This behavior is a result of the selective collapse of the resonances corresponding to the four copper sites in the unit cell produced by the exchange interactions between the copper ions. The magnitudes of the exchange interactions between the copper ions were evaluated from the angular variation of the line width and the collapse of the EPR lines. The value |JAD/kB| = 0.8 K between neighboring copper atoms at 4.942 Å is assigned to a syn-anti equatorial-apical carboxylate bridge with a total bond length of 6.822 Å, while the small value |J AB/kB| = 0.004 K is assigned to a long bridge of 11 atoms with a total bond length of 19.186 Å, that includes one resonance assisted hydrogen bond (RAHB). This finding is discussed in terms of values obtained for similar paths in other model compounds and in proteins.

AB - EPR measurements have been performed on single crystals of [Cu(L-tyrosine)2]az at 33.8 GHz and at room temperature. The EPR spectra display partially resolved EPR lines for most orientations of the magnetic field in the ab plane, and only one resonance for orientations close to the crystal axes, while only a single line is observed along any direction in the ca and cb crystal planes. This behavior is a result of the selective collapse of the resonances corresponding to the four copper sites in the unit cell produced by the exchange interactions between the copper ions. The magnitudes of the exchange interactions between the copper ions were evaluated from the angular variation of the line width and the collapse of the EPR lines. The value |JAD/kB| = 0.8 K between neighboring copper atoms at 4.942 Å is assigned to a syn-anti equatorial-apical carboxylate bridge with a total bond length of 6.822 Å, while the small value |J AB/kB| = 0.004 K is assigned to a long bridge of 11 atoms with a total bond length of 19.186 Å, that includes one resonance assisted hydrogen bond (RAHB). This finding is discussed in terms of values obtained for similar paths in other model compounds and in proteins.

KW - Biomolecules

KW - Copper complexes

KW - EPR spectroscopy

KW - Exchange interaction

KW - Model systems

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U2 - 10.1016/j.jinorgbio.2012.04.013

DO - 10.1016/j.jinorgbio.2012.04.013

M3 - Article

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JO - Journal of Inorganic Biochemistry

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