四面体Ni ((II) Se4コーディネーション複合体における非常に大きなゼロフィールド分裂の直接観測
Shang-Da Jiang1, Dimitrios Maganas2, Nikolaos Levesanos3
11. Physikalisches Institut, Universität Stuttgart , Pfaffenwaldring 57, D-70550, Stuttgart, Germany.
Journal of the American Chemical Society
|September 10, 2015
まとめ
研究者は磁気計とスペクトロスコーピーを用いて高スピンニッケル (II) 複合体を研究した. 彼らは例外的に大きなゼロフィールド分割 (zfs) 値を発見し,電子構造と磁気特性についての洞察を提供した.
科学分野:
- 無機化学
- 量子化学について
- マグネト化学
背景:
- 高スピンニッケル (II) 複合体は,そのユニークな電子および磁気特性のために興味があります.
- ゼロフィールド分裂 (zfs) は,移行金属複合体の磁気行動に影響を与える重要なパラメータである.
研究 の 目的:
- 高スピンの四面体Ni (II) 複合体の磁気と電子の性質を調査する.
- ゼロフィールド分割 (zfs) パラメータを正確に決定し,その起源を理解する.
主な方法:
- マグネトメトリーで磁化軸を測定する.
- 遠赤外線磁気スペクトロスコーピーは,スピンサブレベル移行を直接観察します.
- 電子構造を測るための量子化学計算
主要な成果:
- 複合体は例外的に大きなzfs値を示した (D = 45.40cm ((-1),E = 1.91cm ((-1)).
- これらは,高スピンのNi (II) 複合体に対して直接決定された最大のzfs値である.
- Ab initio計算では,ニオンのスピン軌道結合がDの支配的要因であることが明らかになった.
結論:
- この研究は,高回転のNi (II) 複合体の記録的なzfs値を報告しています.
- 電子構造と磁性アニソトロピーは主にNiイオンスピン軌道結合によって制御される.
- zfsへのセレニウムの貢献は,かなり小さいことが判明しました.
関連する概念動画
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
49.7K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
49.7K
02:58Crystal Field Theory - Octahedral Complexes
31.8K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
31.8K
02:57Coordination Number and Geometry
19.9K
For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
19.9K
02:42Valence Bond Theory
11.7K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
11.7K
03:02Colors and Magnetism
14.6K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
14.6K
01:13¹H NMR: Complex Splitting
2.2K
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
2.2K