xraytools.

Isotope Pattern

https://xraytools.com/isotopes?formula=SnCl4

No diffraction data

The distribution of molecular masses that the natural isotopic composition of the elements produces — the M, M+1, M+2 series a mass spectrum shows — together with the monoisotopic and average mass.

You supply
A chemical formula, in the same grammar every other page here uses. Whole atoms only: a pattern describes one molecule, so a fractional stoichiometry is refused rather than rounded. Write a charge into the formula (SO4^2-, Na+) and every mass becomes m/z, electron mass included.
Reading it
This is an exact combinatorial result, not a simulated spectrum: no resolution, no peak shape, no adducts and no fragmentation. Which peak is tallest is not the monoisotopic one for tin or a polybrominated compound, and the chart says what its heights are measured against.

Worked examples: a nickel complex · dibromomethane · tin tetrachloride · a sulfate anion

See also: Absorption Coefficient Calculator · CHN Calculator

What each input changes
Show peaks above
The floor, as a percentage of the tallest peak, below which a peak is left out of the table. Between 0.001 and 100: above 100 nothing would be listed, and at 0 a large molecule lists thousands of combinations no spectrometer separates.

Input

Write the charge into the formula if you want m/z: SO4^2-, [Fe(CN)6]^3-, Na+.

% of the tallest

A height relative to the tallest peak, so it runs from 0.001 to 100 %. Lower it to see the weak peaks; raise it to see only the ones an instrument would pick out.

Results

formula: SnCl4
monoisotopic mass: 259.7776
average mass: 260.5219
base peak: 259.7753

Pattern

Isotope pattern, 15 peaks. The table below carries the same numbers.0255075100251.7802 Da, 252 nucleons: 1.34 % of the base peak, 0.320 % of the whole pattern251.7802 · 1.3 %253.7776 Da, 254 nucleons: 2.62 % of the base peak, 0.626 % of the whole pattern253.7776 · 2.6 %255.7769 Da, 256 nucleons: 22.01 % of the base peak, 5.264 % of the whole pattern255.7769 · 22.0 %256.7782 Da, 257 nucleons: 11.18 % of the base peak, 2.673 % of the whole pattern256.7782 · 11.2 %257.7757 Da, 258 nucleons: 59.72 % of the base peak, 14.284 % of the whole pattern257.7757 · 59.7 %258.7769 Da, 259 nucleons: 25.66 % of the base peak, 6.137 % of the whole pattern258.7769 · 25.7 %259.7753 Da, 260 nucleons: 100.00 % of the base peak, 23.918 % of the whole pattern259.7753 · 100.0 %260.7748 Da, 261 nucleons: 21.70 % of the base peak, 5.190 % of the whole pattern260.7748 · 21.7 %261.7739 Da, 262 nucleons: 86.93 % of the base peak, 20.792 % of the whole pattern261.7739 · 86.9 %262.7723 Da, 263 nucleons: 8.66 % of the base peak, 2.071 % of the whole pattern262.7723 · 8.7 %263.7736 Da, 264 nucleons: 48.28 % of the base peak, 11.547 % of the whole pattern263.7736 · 48.3 %264.7697 Da, 265 nucleons: 1.66 % of the base peak, 0.397 % of the whole pattern264.7697 · 1.7 %265.7740 Da, 266 nucleons: 20.35 % of the base peak, 4.868 % of the whole pattern265.7740 · 20.4 %267.7735 Da, 268 nucleons: 6.20 % of the base peak, 1.484 % of the whole pattern267.7735 · 6.2 %269.7715 Da, 270 nucleons: 1.11 % of the base peak, 0.266 % of the whole pattern269.7715 · 1.1 %255260265270mass / Darelative abundance / %
Every peak of the pattern above, and the isotopes that make it. CSV
massnucleonsrelative / %abundance / %made of
251.7802 252 1.34 0.320 112Sn 100.0 %
253.7776 254 2.62 0.626 112Sn + 37Cl 65.3 %, 114Sn 34.7 %
255.7769 256 22.01 5.264 116Sn 91.0 %, 114Sn + 37Cl 5.3 %, 2 37Cl + 112Sn 3.7 %
256.7782 257 11.18 2.673 117Sn 94.6 %, 115Sn + 37Cl 5.4 %
257.7757 258 59.72 14.284 118Sn 55.9 %, 116Sn + 37Cl 42.9 %, 2 37Cl + 114Sn 0.9 %, 3 37Cl + 112Sn 0.3 %
258.7769 259 25.66 6.137 117Sn + 37Cl 52.8 %, 119Sn 46.1 %, 2 37Cl + 115Sn 1.1 %
259.7753 260 100.00 23.918 monoisotopic 44.9 %, 118Sn + 37Cl 42.7 %, 2 37Cl + 116Sn 12.3 %, 3 37Cl + 114Sn 0.1 %
260.7748 261 21.70 5.190 119Sn + 37Cl 69.8 %, 2 37Cl + 117Sn 29.9 %, 3 37Cl + 115Sn 0.3 %
261.7739 262 86.93 20.792 37Cl 66.1 %, 2 37Cl + 118Sn 23.6 %, 122Sn 7.3 %, 3 37Cl + 116Sn 3.0 %
262.7723 263 8.66 2.071 2 37Cl + 119Sn 83.9 %, 3 37Cl + 117Sn 16.0 %, 4 37Cl + 115Sn 0.1 %
263.7736 264 48.28 11.547 2 37Cl 57.1 %, 122Sn + 37Cl 16.9 %, 124Sn 16.5 %, 3 37Cl + 118Sn 9.1 %, other combinations 0.4 %
264.7697 265 1.66 0.397 3 37Cl + 119Sn 93.3 %, 4 37Cl + 117Sn 6.7 %
265.7740 266 20.35 4.868 124Sn + 37Cl 50.1 %, 3 37Cl 28.9 %, 2 37Cl + 122Sn 19.2 %, 4 37Cl + 118Sn 1.7 %
267.7735 268 6.20 1.484 2 37Cl + 124Sn 79.0 %, 3 37Cl + 122Sn 13.5 %, 4 37Cl 7.6 %
269.7715 270 1.11 0.266 3 37Cl + 124Sn 94.0 %, 4 37Cl + 122Sn 6.0 %

These are the relative abundances that follow from the natural isotopic composition of the elements — an exact combinatorial result, not a simulated spectrum. There is no instrument here: no resolution, no peak shape, no adducts and no fragmentation. Combinations with the same number of nucleons are shown as one peak at their abundance-weighted mass, which is what an instrument of ordinary resolving power sees; at high resolution several of these would split. Abundances are relative to the tallest peak, which is not always the monoisotopic one. Point at a peak or at its row to mark both; click to keep it marked, and click it again or press Escape to let go.

The last column names the isotope substitutions each peak is made of, as percentages of that peak, counted from the composition in which every element takes its most abundant nuclide — the same composition the monoisotopic mass is defined from. Two substitutions with the same nucleon count are one peak here and two different molecules in a high-resolution spectrum. Where a peak has more combinations than the column lists, the rest are summed as other combinations, so the percentages always add up to 100.

Where this comes from