# Pressure-temperature stable conditions of the hydride-ion conductive phase in BaH                    <sub>2</sub>                    and SrH                    <sub>2</sub>

https://mdr.nims.go.jp/datasets/ca1c1d1c-fd79-443f-96f1-db2063cffa66

## File

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## Id

ca1c1d1c-fd79-443f-96f1-db2063cffa66

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2026-07-09T02:00:41.288771Z

## Updated at

2026-07-09T23:46:57.063749Z

## Published at

2026-07-10T01:24:21.652841Z

## Doi



## First published url

https://doi.org/10.1080/14686996.2026.2691690

## Date published

2026-12-31

## Recorded date published

2026-12-31

## Resource type

journal_article

## Manuscript type

vor

## Collection



## Title

- title: |-
    Pressure-temperature stable conditions of the hydride-ion conductive phase in BaH
                        <sub>2</sub>
                        and SrH
                        <sub>2</sub>
  title_type: original
  lang: en

## Description

- description: The high-pressure (HP)/high-temperature (HT) phase diagram of barium
    hydride (BaH2) was investigated using X-ray diffraction measurements and diamond-anvil
    cells to clarify the relationships between some phases, including the hydride-ion
    (H–) conductive HT phase that adopts the Ni2In-type structure. The results revealed
    that the HT phase and the HP phase were the same in the phase diagram and constitute
    an HP/HT phase. Furthermore, it was found that the Ni2In-type structure is stable
    over a wide range up to approximately 50 GPa and 500 ℃. The coexistence of two
    phases during the phase transition may be responsible for the previously reported
    anomalous pressure dependency of ionic conductivity in the HP phase. Additionally,
    the HP/HT phase diagram of strontium hydride (SrH2), which exhibits a similar
    HP structural sequence, was also investigated. It was found that the Ni2In-type
    structure of SrH2 is stable at pressures above 7 GPa within the temperature range
    of this work (~500 ℃). These wide stable HP/HT regions imply that the structural
    properties of hydride-ion conductive BaH2 and SrH2 can be investigated under the
    wide conditions in the future. Furthermore, the pressure dependence of the lattice
    parameters and volume was obtained, and the bulk moduli of BaH2 and SrH2 in the
    Ni2In-type structure are determined to be 31.5(15) GPa and 42.4(7) GPa, respectively.
    The pressure dependence of the crystallographic parameters obtained in this study
    will be useful for understanding the origin of the properties from the crystallographic
    viewpoint in future work.
  description_type: abstract
  lang: und

## Creator

- name: Satoshi Nakano
  role: author
  orcid: https://orcid.org/0000-0002-7010-9867
- name: Hiroshi Fujihisa
  role: author
  orcid: https://orcid.org/0000-0001-9308-153X
- name: Hiroshi Yamawaki
  role: author
  orcid: https://orcid.org/0000-0002-0145-9935
- name: Yuki Shibazaki
  role: author
  orcid: https://orcid.org/0000-0002-0550-6719
- name: Takumi Kikegawa
  role: author
  orcid: https://orcid.org/0000-0001-8207-9987
- name: Shin-Ichi Orimo
  role: author
  orcid: https://orcid.org/0000-0002-4216-0446

## Contact agent



## Publisher

organization: Informa UK Limited

## Managing organization



## Keyword

- subject: barium hydride
  schema: not_defined
- subject: strontium hydride
  schema: not_defined
- subject: hydride-ion conduction
  schema: not_defined
- subject: high-pressure and high-temperature
  schema: not_defined
- subject: phase diagram
  schema: not_defined

## Rights

- identifier: https://creativecommons.org/licenses/by/4.0/

## Other identifier(s)



## Data origin



## Embargo



## Journal

- title: Science and Technology of Advanced Materials
  issn: '14686996'
  volume: '27'
  issue: '1'
  article_number: '2691690'

## Conference



## Related item



## Funding

- identifier: 24K01445 and 25K01508
  funder_name: MEXT/JSPS KAKENHI
- identifier: JPMXP0112101001
  funder_name: Tokodai Institute for Elemental Strategy, MEXT Element Strategy Initiative
    to Form Core Research Center, Japan
- identifier: JP18K05284
  funder_name: MEXT/JSPS KAKENHI
- identifier: JP21H00030
  funder_name: MEXT/JSPS KAKENHI
- identifier: 24K01427
  funder_name: MEXT/JSPS KAKENHI

## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



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## Custom property



## Fileset

- id: f25b8a00-ed7f-40ad-a184-930aa982b632
  filename: Pressure-temperature stable conditions of the hydride-ion conductive phase
    in BaH2 and SrH2.pdf
  content_type: application/pdf
  size: 6179754
  md5: 53c8d9dc3cfb4eca023a7e37d8edaf90
- id: f60bc24a-4732-480b-9d66-bbdadfa025dc
  filename: tsta_a_2691690_sm0610.pdf
  content_type: application/pdf
  size: 303652
  md5: 94526ba3ced2cb98eeb6167a3cf9989b

## Thumbnail

fileset_id: f25b8a00-ed7f-40ad-a184-930aa982b632
filename: Pressure-temperature stable conditions of the hydride-ion conductive phase
  in BaH2 and SrH2.pdf