K4P2O7
Potassium pyrophosphate · Tetrapotassium pyrophosphate, TKPP
Potassium pyrophosphate is a stable, insulating inorganic salt commonly used as a cleaning agent, food additive, and water treatment chemical.
About Potassium pyrophosphate
Potassium pyrophosphate is a thermodynamically stable inorganic salt characterized by its wide-band-gap insulating electronic properties. It serves as a versatile chemical agent due to its ability to interact with metal ions in aqueous solutions.
This compound is highly valued in industrial applications for its effectiveness as a builder in detergents and as a stabilizer in food processing. Its structural reliability and chemical behavior make it a fundamental component in various cleaning and manufacturing formulations.
Key Properties
Cross-validated computational properties for Potassium pyrophosphate, aggregated across 3 databases.
Band GapEnergy needed to move an electron from the valence band to the conduction band. Lower or zero values tend to behave more metallic; larger gaps are more insulating or semiconducting.
Energy Above HullThermodynamic distance from the most stable set of competing phases. 0 eV/atom is on the convex hull; small positive values may still be experimentally accessible.
StabilityA plain-language summary of the best reported energy-above-hull result. It reflects whether the lowest-energy structure is on, near, or far from the stability hull.
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
Cross-Source DFT Agreement
How well independent DFT databases agree on the thermodynamics of K4P2O7. Tight agreement means computed properties can be trusted without re-running calculations.
Agreement ScoreA normalized confidence score summarizing how closely independent DFT databases agree. Higher scores mean tighter cross-source agreement.
Hull SpreadDifference between the highest and lowest energy-above-hull values reported by comparable sources. Smaller spread means less thermodynamic disagreement.
Sources ComparedNumber and names of computational sources with comparable entries for this formula.
Space Group ConsensusWhether independent sources predict the same crystal symmetry for the lowest-energy structure.
Reported Structures
Lowest-energy structures reported for K4P2O7, ranked by energy above hull.
| Space GroupSymmetry classification of the crystal arrangement. The number is the international space-group index. | Crystal SystemBroad lattice family, such as cubic, tetragonal, monoclinic, or triclinic, derived from unit-cell symmetry. | Band Gap (eV)Electronic gap calculated for this specific reported structure, measured in electronvolts. | E above hull (eV/atom)Thermodynamic distance from the convex hull for this structure, normalized per atom. Lower is generally more stable. | E/atom (eV)Computed total energy normalized per atom. Use energy above hull, not this value alone, when comparing stability. | Density (g/cm³)Mass per relaxed crystal volume, reported in grams per cubic centimeter. |
|---|---|---|---|---|---|
| — | — | 4.78 | 0.0000 | -2.522 | — |
| P63/mmc (No. 194) | hexagonal | 3.77 | 0.0000 | -2.366 | — |
| P63/mmc (No. 194) | hexagonal | 3.74 | 0.0000 | -6.451 | 2.45 |
| — | — | 4.99 | 0.0176 | -2.505 | — |
| — | — | 4.25 | 0.0958 | -2.427 | — |
| P61 (No. 169) | hexagonal | — | — | — | 2.56 |
| P63/mmc (No. 194) | hexagonal | — | — | — | 2.46 |
| P63/mmc (No. 194) | hexagonal | — | — | — | 2.40 |
| P63/mmc (No. 194) | hexagonal | — | — | — | 2.46 |
| P63/mmc (No. 194) | hexagonal | — | — | — | 2.32 |
| P63/mmc (No. 194) | hexagonal | — | — | — | 2.37 |
Applications
Where Potassium pyrophosphate is used.
Frequently Asked Questions
Common questions about Potassium pyrophosphate, answered from cross-validated data.
What is K4P2O7?
Potassium pyrophosphate is a stable, insulating inorganic salt commonly used as a cleaning agent, food additive, and water treatment chemical.
What is K4P2O7 used for?
What is the band gap of K4P2O7?
Is K4P2O7 a metal, semiconductor, or insulator?
Is K4P2O7 thermodynamically stable?
What is the crystal structure of K4P2O7?
How many polymorphs of K4P2O7 are known?
What elements does K4P2O7 contain?
Where does the data for K4P2O7 come from?
How It Compares
As a prominent inorganic pyrophosphate, this compound represents a key example of stable alkali metal phosphate chemistry, serving as a benchmark for solubility and sequestering performance in its class.
Data sources & attribution
- oqmd — Data from the OQMD (oqmd.org). Cite: Saal et al., JOM 65, 1501 (2013); Kirklin et al., npj Comp. Mater. 1, 15010 (2015). (CC-BY-4.0)
- jarvis — Data from JARVIS (jarvis.nist.gov), NIST. Cite: Choudhary et al., npj Comp. Mater. 6, 173 (2020). (LicenseRef-US-Gov-PD)
- materials_project — Data from the Materials Project (materialsproject.org). Cite: Jain et al., APL Materials 1, 011002 (2013). (CC-BY-4.0)
- cod — Data from the Crystallography Open Database (crystallography.net/cod/). Cite: Grazulis et al., J. Appl. Cryst. 42, 726 (2009). (CC0-1.0)
- mpaloe — Data from MP-ALOE. Cite: Kuner et al., npj Comput. Mater. (2025), doi:10.1038/s41524-025-01834-9.
Analyze K4P2O7 in the Lattice Graph platform
Polymorph comparison, confidence scoring, supply-chain risk, and patent monitoring — across 85 source databases.
Explore the Platform →