Beryllium phosphide (BeP2) (57620-29-8) Physical and Chemical Properties
Beryllium phosphide (BeP2)
Inorganic binary phosphide used as a specialty material and reagent in solid‑state and materials‑science research and small‑scale synthesis.
| CAS Number | 57620-29-8 |
| Family | Metal phosphides |
| Typical Form | Powder or crystalline solid |
| Common Grades | EP |
Beryllium phosphide is an inorganic binary phosphide of beryllium and phosphorus that crystallizes as an ionic/covalent extended solid. The compound exists according to computed descriptors as \(\ce{Be3P2}\) (IUPAC: triberyllium bis(phosphorus(3-))), and the bulk solid is best described as a lattice of small, highly polarizing \(\ce{Be^2+}\) centers coordinated to more polarizable \(\ce{P^3-}\) anions. Bonding in such alkaline‑earth phosphides contains significant ionic character with partial covalency arising from polarization by the small Be2+ cation and the multivalent nature of P3-.
Chemically, phosphide anions are strongly basic and highly nucleophilic; they undergo facile protonation/hydrolysis in contact with protic media to give phosphine and hydroxide-containing beryllium species. The material is therefore chemically reactive toward water, acids and other protic reagents; in inert, anhydrous conditions it is substantially more stable. Electronic structure considerations and the stoichiometry \(\ce{Be3P2}\) indicate a wide bandgap, insulating to semiconducting character typical of many metal phosphides, which can make such phases of interest in fundamental solid‑state and materials research.
Common commercial grades reported for this substance include: EP.
Basic Physical Properties
Density
No experimentally established value for this property is available in the current data context.
Melting or Decomposition Point
No experimentally established value for this property is available in the current data context.
Solubility in Water
No experimentally established value for solubility is available in the current data context. Qualitatively, \(\ce{Be3P2}\) reacts with water (hydrolyzes) rather than simply dissolving; the representative hydrolysis reaction is: \( \ce{Be3P2 + 6 H2O -> 3 Be(OH)2 + 2 PH3} \). Hydrolysis therefore produces gaseous phosphine (\(\ce{PH3}\)) and beryllium hydroxide species; these reaction pathways dominate the observed behavior on contact with moist environments.
Solution pH (Qualitative Behavior)
No experimentally established numeric \(\mathrm{pH}\) value is available for aqueous solutions because the compound hydrolyzes on contact with water. Hydrolysis generates hydroxide anions and thus tends to produce alkaline conditions in the remaining aqueous phase while evolving phosphine gas.
Chemical Properties
Acid–Base Behavior
The phosphide anion (\(\ce{P^3-}\)) is a strong Bronsted base in protic media and is readily protonated in stepwise fashion to give phosphine (\(\ce{PH3}\)). In the solid state the anion is stabilized by lattice interactions with \(\ce{Be^2+}\), but exposure to acids or water results in protonation and cleavage of the lattice with release of reduced phosphorus species. Beryllium in its divalent state exhibits amphoteric behavior in many compounds (forming hydroxides that can react with both acids and strong bases), which influences the identity of soluble products after hydrolysis.
Reactivity and Stability
Beryllium phosphide is chemically unstable toward protic reagents, including water and common acids, with evolution of toxic and flammable phosphine. It will also react with strong oxidants to produce oxidized phosphorus species. Under dry, inert conditions the solid is comparatively stable; elevated temperatures can promote decomposition or oxidation depending on atmosphere. No experimentally established decomposition temperature is available in the current data context.
Molecular and Ionic Parameters
Formula and Molecular Weight
- Molecular formula: \(\ce{Be3P2}\)
- IUPAC name (computed): triberyllium bis(phosphorus(3-))
- Molecular weight: 88.984073 \(\mathrm{g}\,\mathrm{mol}^{-1}\)
- Exact mass: 88.984073
- Monoisotopic mass: 88.984073
Computed structural descriptors:
- Heavy atom count: 5
- Hydrogen bond donor count: 0
- Hydrogen bond acceptor count: 2
- Rotatable bond count: 0
- Topological polar surface area (TPSA): 0
- Formal charge: 0
- Complexity: 0
Constituent Ions
The compound consists stoichiometrically of \(\ce{3Be^2+}\) and \(\ce{2P^3-}\) ions in the extended lattice. The formal ionic stoichiometry may be written as the neutral aggregate \(\ce{Be3P2}\); however, local bonding features include polarization and partial covalency due to the small size and high charge density of \(\ce{Be^2+}\).
Identifiers and Synonyms
Registry Numbers and Codes
- CAS number: 57620-29-8
- EC number: 261-137-1
- InChI:
InChI=1S/3Be.2P/q3*+2;2*-3 - InChIKey:
JQJOLPDVNHLLKT-UHFFFAOYSA-N - SMILES:
[Be+2].[Be+2].[Be+2].[P-3].[P-3]
Synonyms and Common Names
Reported names and synonyms include:
- Beryllium phosphide (BeP2)
- Beryllium phosphide
- \(\ce{Be3P2}\)
- BeP2
- triberyllium phosphorus(3-)
- IUPAC/computed: triberyllium bis(phosphorus(3-))
Industrial and Commercial Applications
Functional Roles and Use Sectors
Metal phosphides as a class are encountered in materials science research (semiconductor and electronic materials), in high‑temperature ceramics and refractory phases, and as precursors for generation of phosphine in controlled synthetic contexts. Beryllium phosphide, specifically, may be studied as a structural or electronic material in research settings where beryllium‑containing phosphides are of interest.
Typical Application Examples
No concise application summary is available in the current data context; in practice this substance is selected based on its general properties described above (solid-state ionic/covalent lattice, reactivity toward protic media, and potential electronic properties).
Safety and Handling Overview
Health and Environmental Hazards
- Contains beryllium: beryllium compounds are associated with serious chronic respiratory toxicity (sensitization and chronic beryllium disease) on inhalation of dusts or aerosols; they are handled with strict controls in occupational settings.
- Produces phosphine on hydrolysis: phosphine (\(\ce{PH3}\)) is acutely toxic, flammable and can be pyrophoric in air under some conditions.
- Environmental persistence and bioavailability depend on form and dispersion; avoid release to the environment and control dusts.
Storage and Handling Considerations
- Store in a dry, well‑sealed container under inert atmosphere or desiccant control to prevent hydrolysis and phosphine evolution.
- Avoid contact with water, acids, and oxidizing agents.
- Implement engineering controls to minimize dust and airborne particulate exposure (local exhaust ventilation, enclosed systems).
- Use appropriate personal protective equipment (PPE): gloves, eye protection and respiratory protection where airborne exposure may occur.
- Segregate from incompatible materials (protic media, strong acids, oxidizers).
- For detailed hazard, transport and regulatory information, users should refer to the product‑specific Safety Data Sheet (SDS) and local legislation.
