Band vs. polaron: vibrational motion and chemical expansion of hydride ions as signatures for the electronic character in oxyhydride barium titanate

Erik Jedvik Granhed; Anders Lindman; Carin Eklöf-Österberg; Maths Karlsson; Stewart F. Parker; Göran Wahnström

doi:10.1039/c9ta00086k

The role of oxygen vacancies on the vibrational motions of hydride ions in the oxyhydride of barium titanate

Journal of Materials Chemistry A ◽

10.1039/c9ta11912d ◽

2020 ◽

Vol 8 (13) ◽

pp. 6360-6371 ◽

Cited By ~ 1

Author(s):

Carin Eklöf-Österberg ◽

Laura Mazzei ◽

Erik Jedvik Granhed ◽

Göran Wahnström ◽

Reji Nedumkandathil ◽

...

Keyword(s):

Barium Titanate ◽

Oxygen Vacancies ◽

Dft Study ◽

Vibrational Dynamics ◽

Effect Of Oxygen ◽

Hydride Ions

Combined INS and DFT study on BaTiO3−xHx unravels the effect of oxygen vacancies on the vibrational dynamics of hydride ions.

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DFT STUDY ON CONFORMATIONAL BEHAVIOR OF HYDROGEN ION ABSTRACTIONS OF CYTOSINE NUCLEOSIDES: AIM AND NBO ANALYSIS

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633611006797 ◽

2011 ◽

Vol 10 (06) ◽

pp. 803-817 ◽

Cited By ~ 3

Author(s):

ZAHRA ALIAKBAR TEHRANI ◽

ALIREZA FATTAHI ◽

MARJAN JEBELI JAVAN ◽

MOHAMMAD MAHMOODI HASHEMI

Keyword(s):

Structural Parameters ◽

Nbo Analysis ◽

Basis Sets ◽

Orbital Method ◽

Acceptor Interaction ◽

Hydride Ion ◽

Stability Order ◽

The Stability ◽

Intramolecular Hydrogen ◽

Hydride Ions

In this paper, we explore theoretically energetic and structural properties of the possible cations formed via hydride ion abstraction at various sites of sugar part of cytosine nucleosides by employing B3LYP exchange-correlation functional with 6-311++G (d,p) orbital basis sets. In general, the hydride ion abstracted sugar cations of cytosine nucleosides have the following stability sequence: caH2′ > caH1′ > caH3′ > caH4′ > caH5′ for cytidine and caH1′ > caH4′ > caH3′ > caH5′ > caH2′ for deoxycytidine. Furthermore, the effect of solvent environment on the stability order of cations integral equation formalism of the polarized model (IEF-PCM) was employed to model aqueous solution. The natural bond orbital method was used for quantitative analysis of the electron delocalization donor–acceptor interaction of various hydride ions abstracted centers of cytosine nucleosides. The role of CH⋯O and HO⋯H intramolecular hydrogen bonds in the stability of cations is investigated based on the results of topological properties of atom in molecule theory. Moreover, variations of significant structural parameters such as puckering amplitudes and phase angles of sugar parts of cytosine nucleosides after cation formation are also found.

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The Number of Hydride Ions in AlH2Cl Available for Hydrogenolysis of 1,3-Dioxolanes

Canadian Journal of Chemistry ◽

10.1139/v71-352 ◽

1971 ◽

Vol 49 (12) ◽

pp. 2166-2168 ◽

Cited By ~ 7

Author(s):

H. A. Davis ◽

R. K. Brown

Keyword(s):

Lewis Acid ◽

Intermediate Compound ◽

Acid Base ◽

Base Complex ◽

Hydride Ion ◽

Hydride Ions ◽

Similar Complex

2-Methyl-1,3-dioxolane (1) in ether is hydrogenolyzed completely to 2-ethoxyethanol by an equimolar proportion of AlH2Cl, whereas a 1/2 mol of AlH2Cl hydrogenolyzes 1 mol of 1 only to the extent of 50%. In the latter case, the intermediate compound 2-ethoxyethoxyhydridoaluminum chloride (C2H5OCH2CH2OAlHCl) formed with half of the 2-methyl-1,3-dioxolane, even though it contains a hydride ion, fails to react with the remainder of the dioxolane. This is believed due to the preference of C2H5OCH2CH2OAlHCl to form an internal Lewis acid-base complex rather than form a similar complex with 1, a step essential to facilitate the hydrogenolysis of 1.

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First-Principles Calculations of Point Defect Formation and Anion Diffusion Mechanisms in the Oxyhydride Ba2ScHO3

10.26434/chemrxiv.12121254 ◽

2020 ◽

Cited By ~ 1

Author(s):

Akihide Kuwabara ◽

Fumitake Takeiri ◽

Haq Nawaz ◽

Genki Kobayashi

Keyword(s):

Point Defect ◽

First Principles ◽

Defect Formation ◽

Diffusion Mechanism ◽

Layered Perovskite ◽

First Principles Calculations ◽

Ion Conductor ◽

Hydride Ion ◽

Anion Diffusion ◽

Hydride Ions

<div>Hydride ion conductors are expected to be a new solid electrolyte for electrochemical devices utilizing hydrogen. La<sub>2-x-y</sub>Sr<sub>x+y</sub>LiH<sub>1-x+y</sub>O<sub>3-y</sub> oxyhydride with a layered perovskite (K<sub>2</sub>NiF<sub>4</sub>-type) structure was discovered as a hydride ion conductor, and it was subsequently reported that Ba<sub>2</sub>ScHO<sub>3</sub> with the same crystal structure is also a hydride ion conductor. The two compounds have different anionic sites occupied by hydride ions. In La<sub>2-x-y</sub>Sr<sub>x+y</sub>LiH<sub>1-x+y</sub>O<sub>3-y</sub>, the hydride ions occupy equatorial anion sites, while the hydride ions are located at apical anion sites in Ba<sub>2</sub>ScHO<sub>3</sub>. This suggests that hydride ions diffuse through rock-salt layers in Ba<sub>2</sub>ScHO<sub>3</sub>. However, the specific diffusion mechanism resulting in ionic conductivity of Ba<sub>2</sub>ScHO<sub>3</sub> has not been clarified yet. In the present study, the point defect</div><div>formation energies and anionic conduction mechanisms of Ba<sub>2</sub>ScHO<sub>3</sub> were systematically analyzed using first-principles calculations. As a result, hydride ionic defects tend to form preferentially in Ba<sub>2</sub>ScHO<sub>3</sub> rather than oxide ions. The migration energies of vacancy, interstitial and interstitialcy mechanisms were evaluated, and the activation energies of hydride ionic diffusion mediated by the vacancy and the interstitialcy processes was found to be the lowest.</div>

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First-Principles Calculations of Point Defect Formation and Anion Diffusion Mechanisms in the Oxyhydride Ba2ScHO3

10.26434/chemrxiv.12121254.v2 ◽

2020 ◽

Author(s):

Akihide Kuwabara ◽

Fumitake Takeiri ◽

Haq Nawaz ◽

Genki Kobayashi

Keyword(s):

Point Defect ◽

First Principles ◽

Defect Formation ◽

Diffusion Mechanism ◽

Layered Perovskite ◽

First Principles Calculations ◽

Ion Conductor ◽

Hydride Ion ◽

Anion Diffusion ◽

Hydride Ions

<div>Hydride ion conductors are expected to be a new solid electrolyte for electrochemical devices utilizing hydrogen. La<sub>2-x-y</sub>Sr<sub>x+y</sub>LiH<sub>1-x+y</sub>O<sub>3-y</sub> oxyhydride with a layered perovskite (K<sub>2</sub>NiF<sub>4</sub>-type) structure was discovered as a hydride ion conductor, and it was subsequently reported that Ba<sub>2</sub>ScHO<sub>3</sub> with the same crystal structure is also a hydride ion conductor. The two compounds have different anionic sites occupied by hydride ions. In La<sub>2-x-y</sub>Sr<sub>x+y</sub>LiH<sub>1-x+y</sub>O<sub>3-y</sub>, the hydride ions occupy equatorial anion sites, while the hydride ions are located at apical anion sites in Ba<sub>2</sub>ScHO<sub>3</sub>. This suggests that hydride ions diffuse through rock-salt layers in Ba<sub>2</sub>ScHO<sub>3</sub>. However, the specific diffusion mechanism resulting in ionic conductivity of Ba<sub>2</sub>ScHO<sub>3</sub> has not been clarified yet. In the present study, the point defect</div><div>formation energies and anionic conduction mechanisms of Ba<sub>2</sub>ScHO<sub>3</sub> were systematically analyzed using first-principles calculations. As a result, hydride ionic defects tend to form preferentially in Ba<sub>2</sub>ScHO<sub>3</sub> rather than oxide ions. The migration energies of vacancy, interstitial and interstitialcy mechanisms were evaluated, and the activation energies of hydride ionic diffusion mediated by the vacancy and the interstitialcy processes was found to be the lowest.</div>

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First-Principles Calculations of Point Defect Formation and Anion Diffusion Mechanism in Oxyhydride Ba2ScHO3

10.26434/chemrxiv.12121254.v1 ◽

2020 ◽

Author(s):

Akihide Kuwabara ◽

Fumitake Takeiri ◽

Haq Nawaz ◽

Genki Kobayashi

Keyword(s):

Point Defect ◽

First Principles ◽

Defect Formation ◽

Diffusion Mechanism ◽

Layered Perovskite ◽

First Principles Calculations ◽

Ion Conductor ◽

Hydride Ion ◽

Anion Diffusion ◽

Hydride Ions

<div>Hydride ion conductors are expected to be a new solid electrolyte for electrochemical devices utilizing </div><div>hydrogen. La2-x-ySrx+yLiH1-x+yO3-y oxyhydride with a layered perovskite (K2NiF4-type) structure was </div><div>discovered as a hydride ion conductor, and it was subsequently reported that Ba2ScHO3 with the same </div><div>crystal structure is also a hydride ion conductor. The two compounds have different anionic sites </div><div>occupied by hydride ions. In La2-x-ySrx+yLiH1-x+yO3-y, the hydride ions occupy equatorial anion sites, </div><div>while the hydride ions are located at apical anion sites in Ba2ScHO3. This suggests that hydride ions </div><div>diffuse through rock-salt layers in Ba2ScHO3. However, the specific diffusion mechanism resulting in </div><div>ionic conductivity of Ba2ScHO3 has not been clarified yet. In the present study, the point defect </div><div>formation energies and anionic conduction mechanisms of Ba2ScHO3 were systematically analyzed </div><div>using first-principles calculations. As a result, hydride ionic defects tend to form preferentially in </div><div>Ba2ScHO3 rather than oxide ions. The migration energies of vacancy, interstitial and interstitialcy </div><div>mechanisms were evaluated, and the activation energies of hydride ionic diffusion mediated by the </div><div>vacancy and the interstitialcy processes was found to be the lowest.</div>

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