Optical absorption of transition-metal island films: Correlation interaction between conduction electrons of transition metals

<div>Covalent organic frameworks (COFs) have emerged as an important class of nano-porous crystalline materials with many potential applications. They are intriguing platforms for the design of porous skeletons with special functionality at the molecular level. However, despite their extraordinary properties, it is difficult to control their electronic properties, thus hindering the potential implementation in electronic devices. A new form of nanoporous material, COFs intercalated with first row transition metal is proposed to address this fundamental drawback - the lack of electronic tunability. Using first-principles calculations, we have designed 31 new COF materials <i>in-silico</i> by intercalating all of the first row transition metals (TMs) with boroxine-linked and triazine-linked COFs: COF-TM-x (where TM=Sc-Zn and x=3-5). This is a significant addition considering that only 187 experimentally COFs structures has been reported and characterized so far. We have investigated their structure and electronic properties. Specifically, we predict that COF's band gap and density of states (DOSs) can be controlled by intercalating first row transition metal atoms (TM: Sc - Zn) and fine tuned by the concentration of TMs. We also found that the $d$-subshell electron density of the TMs plays the main role in determining the electronic properties of the COFs. Thus intercalated-COFs provide a new strategy to control the electronic properties of materials within a porous network. This work opens up new avenues for the design of TM-intercalated materials with promising future applications in nanoporous electronic devices, where a high surface area coupled with fine-tuned electronic properties are desired.</div>

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Bond-length distributions for ions bonded to oxygen: Metalloids and post-transition metals

10.26434/chemrxiv.5410921.v2 ◽

2017 ◽

Cited By ~ 1

Author(s):

Olivier Charles Gagné ◽

Frank Christopher Hawthorne

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Metal Ions ◽

Bond Length ◽

Lone Pair ◽

Transition Metal Ions ◽

Oxygen Lone Pair

Bond-length distributions are examined for thirty-three configurations of the metalloid ions and fifty-six configurations of the post-transition-metal ions bonded to oxygen. Lone-pair stereoactivity is discussed.

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Bond-length distributions for ions bonded to oxygen: Metalloids and post-transition metals

10.26434/chemrxiv.5410921 ◽

2017 ◽

Cited By ~ 1

Author(s):

Olivier Charles Gagné ◽

Frank Christopher Hawthorne

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Metal Ions ◽

Bond Length ◽

Lone Pair ◽

Transition Metal Ions ◽

Oxygen Lone Pair

Bond-length distributions are examined for thirty-three configurations of the metalloid ions and fifty-six configurations of the post-transition-metal ions bonded to oxygen. Lone-pair stereoactivity is discussed.

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Electronic properties of quasi two-dimensional transition metals chalcogenides with low-dimensional magnetism

Doklady BGUIR ◽

10.35596/1729-7648-2020-18-7-87-95 ◽

2020 ◽

Vol 18 (7) ◽

pp. 87-95

Author(s):

M. S. Baranava ◽

P. A. Praskurava

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Exchange Interaction ◽

Electronic Properties ◽

Metal Atom ◽

Transition Metal Atom ◽

Two Dimensional ◽

Transition Metal Atoms ◽

Ground Magnetic ◽

Low Dimensional

The search for fundamental physical laws which lead to stable high-temperature ferromagnetism is an urgent task. In addition to the already synthesized two-dimensional materials, there remains a wide list of possible structures, the stability of which is predicted theoretically. The article suggests the results of studying the electronic properties of MAX3 (M = Cr, Fe, A = Ge, Si, X = S, Se, Te) transition metals based compounds with nanostructured magnetism. The research was carried out using quantum mechanical simulation in specialized VASP software and calculations within the Heisenberg model. The ground magnetic states of twodimensional MAX3 and the corresponding energy band structures are determined. We found that among the systems under study, CrGeTe3 is a semiconductor nanosized ferromagnet. In addition, one is a semiconductor with a bandgap of 0.35 eV. Other materials are antiferromagnetic. The magnetic moment in MAX3 is localized on the transition metal atoms: in particular, the main one on the d-orbital of the transition metal atom (and only a small part on the p-orbital of the chalcogen). For CrGeTe3, the exchange interaction integral is calculated. The mechanisms of the formation of magnetic order was established. According to the obtained exchange interaction integrals, a strong ferromagnetic order is formed in the semiconductor plane. The distribution of the projection density of electronic states indicates hybridization between the d-orbital of the transition metal atom and the p-orbital of the chalcogen. The study revealed that the exchange interaction by the mechanism of superexchange is more probabilistic.

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OPTICAL ABSORPTION AND EPR STUDY OF TRANSITION METAL IONS DOPED PHOSPHATE GLASSES

Phosphorus Research Bulletin ◽

10.3363/prb1992.6.0_241 ◽

1996 ◽

Vol 6 (0) ◽

pp. 241-244 ◽

Cited By ~ 6

Author(s):

MOHAMED HAOUARI ◽

HAFEDH BEN OUADA ◽

HASSEN MAAREF ◽

HUBERT HOMMEL ◽

ANDRE PIERRE LEGRAND

Keyword(s):

Transition Metal ◽

Optical Absorption ◽

Metal Ions ◽

Transition Metal Ions ◽

Phosphate Glasses

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COx-free hydrogen production via ammonia decomposition over mesoporous Co/Al2O3 catalysts with highly dispersed Co species synthesized by a facile method

Dalton Transactions ◽

10.1039/d0dt03262j ◽

2021 ◽

Author(s):

Yingqiu Gu ◽

Di Xu ◽

Yun Huang ◽

Zhouyang Long ◽

Guojian Chen

Keyword(s):

Fuel Cells ◽

Hydrogen Production ◽

Transition Metal ◽

Transition Metals ◽

Ammonia Decomposition ◽

Metal Catalyst ◽

Facile Synthesis ◽

Transition Metal Catalyst ◽

Highly Dispersed ◽

Free Hydrogen

Transition metals have been considered as potential catalysts for ammonia decomposition to produce COx-free hydrogen for fuel cells. However, the facile synthesis of transition metal catalyst with small size active...

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Organic synthesis with the most abundant transition metal–iron: from rust to multitasking catalysts

Chemical Society Reviews ◽

10.1039/d0cs00688b ◽

2021 ◽

Author(s):

Sujoy Rana ◽

Jyoti Prasad Biswas ◽

Sabarni Paul ◽

Aniruddha Paik ◽

Debabrata Maiti

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Organic Synthesis ◽

Present Review ◽

Synthetic Chemistry ◽

Late Transition Metals ◽

Iron Chemistry ◽

Late Transition

The promising aspects of iron in synthetic chemistry are being explored for three-four decades as a green and eco-friendly alternative to late transition metals. This present review unveils these rich iron-chemistry towards different transformations.

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Endo- and exohedral chloro-fulleride as η5 ligands: A DFT study on the first-row transition metal complexes

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05612j ◽

2021 ◽

Author(s):

Sebastian Anila ◽

Cherumuttathu Hariharan Suresh

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Dft Study ◽

C60 Fullerene ◽

Ring Fusion ◽

Coordination Modes

C60 fullerene coordinates to transition metals in η2-fashion through its C-C bond at [6,6] ring fusion whereas other coordination modes η3, η4, η5 and η6 are rarely observed. The coordination...

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Transition metal-catalyzed synthesis of spirooxindoles

RSC Advances ◽

10.1039/d1ra00139f ◽

2021 ◽

Vol 11 (13) ◽

pp. 7146-7179

Author(s):

P. V. Saranya ◽

Mohan Neetha ◽

Thaipparambil Aneeja ◽

Gopinathan Anilkumar

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Antimicrobial Agents ◽

Recent Advances ◽

Transition Metal Catalyzed ◽

Metal Catalyzed

Spirooxindoles are used as anticancer-, antiviral-, antimicrobial agents etc. The use of transition metals as catalysts for the synthesis of spirooxindoles is advancing rapidly. Here, we focus on recent advances in transition metal-catalyzed synthesis of spirooxindoles.

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Soluble lanthanide-transition-metal clusters Ln36Co12 as effective molecular electrocatalysts for water oxidation

Chemical Communications ◽

10.1039/d0cc08132a ◽

2021 ◽

Vol 57 (29) ◽

pp. 3611-3614

Author(s):

Rong Chen ◽

Chao-Long Chen ◽

Ming-Hao Du ◽

Xing Wang ◽

Cheng Wang ◽

...

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Synergistic Effect ◽

Water Oxidation ◽

Metal Clusters ◽

Bond Formation ◽

Transition Metal Clusters ◽

Oxidation Activity ◽

Acidic Conditions ◽

Effective Water

The stable 48-metal Ln36Co12 clusters show an effective water oxidation activity under weak acidic conditions because of the synergistic effect between lanthanide and transition metals in O–O bond formation.

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