Robertson chemical kinetics

ADVANTAGES3 · dim 3

SolvSRK wins. At the comparison noise level, SolvSRK beats the best baseline by at least 10 percentage points of survival, or by at least 0.05 balanced score when survival is tied. Use SolvSRK for this class of problem. All verdicts →

The canonical stiff-chemistry benchmark: three autocatalytic species whose rate constants span eleven orders of magnitude. Clean completion is table stakes for implicit methods; the real differentiator is holding up when the right-hand side is perturbed by noise.

Chemistry & reaction kinetics

Problem definition

Robertson (1966); Hairer–Wanner II §IV.1

Math used in the published benchmark cell — so you can confirm the name matches the ODE you expect. Not a runnable fixture.

ẏ₁ = −k₁ y₁ + k₂ y₂ y₃
ẏ₂ =  k₁ y₁ − k₂ y₂ y₃ − k₃ y₂²
ẏ₃ =  k₃ y₂²
Parameters
  • k₁ = 0.04
  • k₂ = 10⁴
  • k₃ = 3×10⁷
Initial condition
y(0) = (1, 0, 0)
Horizon
t ∈ [0, 10⁵]

Classical ROBER rates. Horizon is 10⁵ (not the Hairer 10¹¹ extended endpoint used by a separate catalog variant).

Fingerprint

Spread: extreme

Default noise: clean

Recommendation snapshot

Clean best: SolvSRK (parity with implicit SciPy)

Noisy best: SolvSRK

Coverage

14 solver arms · clean + 5 noise levels

Ranked on survival, precision, and speed

Versions & freeze

Methodology →
Freeze
2026-08-13
libsolvsrk
2.3.0
SciPy
1.14
SUNDIALS
CVODE (bundled backend)

20 seeds/cell default · 14 arms · TRL 4–5 · simulation-lab validated · this page: Robertson chemical kinetics (robertson)

Governed SolvTune benchmark freeze; per-arm medians only. RHS definitions and raw trial rows are not published.

Self-reported by Resonix Labs · not independently verified

Results matrix

Pick an objective and a noise level to rank all arms on survival, median SCD, median nfev, and median wall time. Medians across seeds.

Objective

Best overall trade-off of survival, precision, and speed.

Noise level

#SolverSurvivalSCDnfevWallScore
1SolvSRK
100%
12.6106,041288 ms0.918
2SciPy RadauSciPy
100%
10.52,50349 ms0.869
3CVODE BDFexternal
100%
7.81,26315 ms0.804
4SciPy BDFSciPy
100%
7.51,38239 ms0.798
5SciPy LSODASciPy
100%
7.41,0225 ms0.795
6CVODE Adamsexternal
100%
2.5621,6484.89 s0.679
SciPy RK45SciPy
0%
SciPy DOP853SciPy
0%
SciPy RK23SciPy
0%
Tsit5external
0%

At Clean, best balanced arm is SolvSRK.

Values are medians across seeds, measured by Resonix Labs on Resonix hardware and not independently verified; nfev and wall are on reference lab hardware (indicative). Under injected noise only SolvSRK and the SciPy arms are run. How we measure accuracy → · Verification status →

SolvScout · free

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This page shows one published benchmark cell. SolvScout fingerprints your ODE, compares it to the full corpus, and recommends a solver with the same survival / precision / speed ranking you see here — including when a SciPy arm wins.

SolvSRK · 30-day trial

Run the winner on your machine

SolvSRK is the stiffness-adaptive integrator behind the SolvSRK column in these tables. Create an account, activate a machine, and take a 30-day trial — same binary you'd ship after purchase.

Cite this page

Replace the access date. Pin the freeze ID and library versions when comparing against a later export. Cite it as what it is — a self-reported vendor benchmark, not an independently verified result. The note field says so; please keep it.

@misc{resonix_evidence_robertson_2026,
  title        = {Resonix Evidence Portal: Robertson chemical kinetics},
  author       = {{Resonix Labs (Canada) Inc.}},
  year         = {2026},
  howpublished = {\url{https://resonix.tech/evidence/problems/robertson}},
  note         = {Self-reported vendor benchmark; internally generated by Resonix Labs and not independently verified. Accessed YYYY-MM-DD. Freeze 2026-08-13; libsolvsrk 2.3.0; SciPy 1.14.}
}

Related

TRL 4–5 · simulation-lab validated · 398 problems · 14 solver arms · clean + 5 noise levels

Freeze: 2026-08-13 · scipy 1.14 · libsolvsrk 2.3.0 · Methodology

Self-reported by Resonix Labs · not independently verified · Verification status