HNO
Nitroxyl · Azanone
Nitroxyl is a short-lived and reactive nitrogen-oxygen species that plays a critical role as a signaling molecule in biological systems.
About Nitroxyl
Nitroxyl is a transient and highly reactive chemical species that exists as a wide-gap insulating molecule. Due to its nature as a species residing above the thermodynamic hull, it is inherently unstable and typically exists only as a fleeting intermediate in chemical or biological pathways.
Its significance lies primarily in its potent biological signaling properties, particularly in cardiovascular physiology. Despite its instability, researchers have identified numerous structural configurations, highlighting its complex role in nitrogen chemistry.
Key Properties
Cross-validated computational properties for Nitroxyl, 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 HNO. 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 HNO, 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. |
|---|---|---|---|---|---|
| C2/c (No. 15) | monoclinic | 3.06 | 0.4795 | -5.899 | 1.61 |
| C2/c (No. 15) | monoclinic | 3.12 | 0.4909 | -0.071 | — |
| C2/c (No. 15) | monoclinic | 3.12 | 0.4909 | -0.071 | — |
| Cc (No. 9) | monoclinic | 3.27 | 0.5156 | -5.863 | 1.67 |
| C2/c (No. 15) | monoclinic | 3.42 | 0.5510 | -5.828 | 1.60 |
| Pm (No. 6) | monoclinic | 1.23 | 1.9958 | 1.434 | — |
| P-6m2 (No. 187) | hexagonal | 0.00 | 2.6926 | 2.131 | — |
| P21/c (No. 14) | monoclinic | — | — | — | 1.83 |
| C2/c (No. 15) | monoclinic | — | — | — | 1.78 |
| C2/c (No. 15) | monoclinic | — | — | — | 1.87 |
Applications
Where Nitroxyl is used.
Frequently Asked Questions
Common questions about Nitroxyl, answered from cross-validated data.
What is HNO?
Nitroxyl is a short-lived and reactive nitrogen-oxygen species that plays a critical role as a signaling molecule in biological systems.
What is HNO used for?
What is the band gap of HNO?
Is HNO a metal, semiconductor, or insulator?
Is HNO thermodynamically stable?
What is the crystal structure of HNO?
What is the density of HNO?
How many polymorphs of HNO are known?
What elements does HNO contain?
Where does the data for HNO come from?
How It Compares
As a unique and highly reactive species, nitroxyl stands apart from stable inorganic compounds due to its propensity to rapidly transform. Unlike conventional materials that occupy a ground-state equilibrium, this compound is defined by its transient existence and high chemical potential.
Data sources & attribution
- materials_project — Data from the Materials Project (materialsproject.org). Cite: Jain et al., APL Materials 1, 011002 (2013). (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)
- cod — Data from the Crystallography Open Database (crystallography.net/cod/). Cite: Grazulis et al., J. Appl. Cryst. 42, 726 (2009). (CC0-1.0)
Analyze HNO in the Lattice Graph platform
Polymorph comparison, confidence scoring, supply-chain risk, and patent monitoring — across 85 source databases.
Explore the Platform →