Each element's spectrum is unique, like a fingerprint.
But some element spectra are near doppelgangers when observed visually.
So they're different. But they're similar. But they're different. But they're similar.
Nitrogen and lead, for example, have an uncanny visual resemblance, as do copper and chromium.
About a dozen elements' spectra can be described as a dense swath of green lines and a dense swath of blue/violet lines.
Each of these elements have their lines at slightly different wavelengths, so can be readily distinguished in
an expensive spectroscope, but the eye does not measure wavelengths so precisely.
Most of the elements in the Interactive Viewer now include links to their closest lookalikes, making it easy to compare and contrast spectra that are similar in appearance.
2021-06-18: For some reason, hackers think it's worth their while to try and break this website.
It's your standard issue SQL injection stuff, basically the laziest kind of hacking that every website should protect itself from at bare minimum -
and a great many sites don't!!!
Peeking at the logs a few days ago I found this gem:
188.8.131.52 2021-06-13 12:27:26 spectrum.php?elem=N Ior 0=0``/">'/*!13337or*/'256'='4'
Yeah n00b, you think you're leet. But you're not. 😂
2021-05-23: In the Interactive Viewer, most spectra that have a photo now have a link underneath that reads "expand". If you click on it, the photo will automagically resize and reposition itself to line up with the generated lines image.
2021-05-20: Over the past few days, I've significantly upgraded my camera setup and taken much more detailed photos of many of the element spectra. A few of them (notably Mn, Pr, and Nd) show a definite variance from the old photo. Not sure why this is, but there's every reason to trust the new detailed photos vs. the old blurry ones. Due to work obligations, social plans, and health conditions, it may take me a while to get everything in sync to the better data: the photographic periodic table for instance, and the guide for learning to identify spectra. The periodic table is also on Wikimedia Commons, along with my photos of individual element spectra, most of which have to be updated, so that is also part of the same workload.
2021-05-15: The new flash cards are now provided on their own for memorization; no pressure to answer any cryptic "what element is this" screens, and you can exit at any time.
2021-05-10: Here's a new guide for recognizing spectra visually. Sure, there are almost 100 spectra to become familiar with, but this will greatly simplify the ones you're likely to ever encounter. It starts off simple and makes clarifying comparisons and descriptions all the way through.
2021-05-02: Great news! This site now offers line tables for all the spectra featured in the various pages and web apps. It uses wavelength data from NIST's Atomic Spectra Database, combined with intensity adjustments to more accurately reflect the perceptual brightnesses of visible lines. It also includes upper and lower energy level information for a great many lines.
2021-04-11: The Identification Game has been revamped with easier hints and a range of difficulty levels. It's a great way to learn to recognize the spectra, and the hints are always available so you're never stranded on an unfamiliar spectrum. And if you win, there's a cool surprise at the end.
2021-03-31: I have procured samples of most of the elements and added photos of their spectra, in order to verify the relative intensities of the brightest lines. The line intensities from my source data have been adjusted accordingly. I still have a few gas tubes to obtain, which should not differ much from the current data. I am also looking into rare and hard to find metals as my budget allows. The samples have to be held by two ordinary alligator clips so I can spark them and take the photos. As my remaining not-yet-ordered metals are all very expensive, they cost a lot for even the small quantities necessary for my experiment, so this part is taking me longer than I would have liked.
2021-03-23: I have noticed a lot of people are still using the old legacy image on their sites. (Understandable, since it existed unchanged for several years.) There's no reason you can't, just be aware it has some huge inaccuracies in it. If you have a copy of the old image, please consider replacing it with a current one. You can still find the old image here if you so desire. Meanwhile, the final image will be ready before too long, and it will differ very little from the current image.
High Resolution Version
Periodic table format
and Photographic Periodic Table
Runs entirely in browser - no download, no risk.
Due to frequent updates to the data, you may notice variances in the table above vs. the high res version v. the interactive version. When in doubt, the interactive version is always the most up to date.
This image is based on spectrum line positions and intensities from MIT Wavelength Tables (1938) and the NIST Atomic Spectrum Database. Most of the spectra have had intensity corrections applied in order to match actual spectrum photos of samples of each element.
Astatine is missing from this image as no visible lines of this element are known. Some lines of francium have been extrapolated from known energy levels.
Disclaimer: Spectra that have not been photographed might not look exactly like the image above. Some spectra may deviate considerably from the depictions pictured here. We are photographing as many element spectra as possible in order to confirm the line intensities of the source data. For most of the actinides, only a few bright lines are known, but the actual spectra should be about as complex as their corresponding lanthanides (compare actinium with thorium or plutonium with uranium and samarium), we just don't have data for most of the lines. Spectra that have been photographed do for certain look like the image above. Spectra not yet photographed or not sufficient quality image include: B, F, P, S, Cl, Se, Br, Rb, Tc, Cs, Pm, Po, Rn, Fr, Ra, and all of the actinides except U. All of these spectra should be treated as suspect in the image above.
The element spectrum images on this page, including the linked high resolution version and the periodic table format image, are Public Domain or CC0.