This notation is so confusing! People often don't manage to explain the intuition behind it, why this is an useful notation. When you see Indian university entry exam level memorization classes about this, it makes you want to cry.
The key reason why term symbols matter are Hund's rules, which allow us to predict with some accuracy which electron configurations of those states has more energy than the other.
web.chem.ucsb.edu/~devries/chem218/Term%20symbols.pdf puts it well: electron configuration notation is not specific enough, as each such notation e.g. 1s2 2s2 2p2 contains several options of spins and z angular momentum. And those affect energy.
This is why those symbols are often used when talking about energy differences: they specify more precisely which levels you are talking about.
Basically, each term symbol appears to represent a group of possible electron configurations with a given quantum angular momentum.
We first fix the energy level by saying at which orbital each electron can be (hyperfine structure is ignored). It doesn't even have to be the ground state: we can make some electrons excited at will.
The best thing to learn this is likely to draw out all the possible configurations explicitly, and then understand what is the term symbol for each possible configuration, see e.g. term symbols for carbon ground state.
It also confusing how uppercase letters S, P and D are used, when they do not refer to orbitals s, p and d, but rather to states which have the same angular momentum as individual electrons in those states.
It is also very confusing how extremelly close it looks to spectroscopic notation!
The form of the term symbol is:
Atomic Term Symbols by TMP Chem (2015)
Source. Atomic Term Symbols by T. Daniel Crawford (2016)
Source. Bibliography:
- chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Spectroscopy/Electronic_Spectroscopy/Spin-orbit_Coupling/Atomic_Term_Symbols
- chem.libretexts.org/Courses/Pacific_Union_College/Quantum_Chemistry/08%3A_Multielectron_Atoms/8.08%3A_Term_Symbols_Gives_a_Detailed_Description_of_an_Electron_Configuration The PDF origin: web.chem.ucsb.edu/~devries/chem218/Term%20symbols.pdf
- chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Inorganic_Coordination_Chemistry_(Landskron)/08%3A_Coordination_Chemistry_III_-_Electronic_Spectra/8.01%3A_Quantum_Numbers_of_Multielectron_Atoms
- physics.stackexchange.com/questions/8567/how-do-electron-configuration-microstates-map-to-term-symbols How do electron configuration microstates map to term symbols?
Bibliography:
CIA 2010 covert communication websites Expired domain trackers Updated 2025-06-17 +Created 1970-01-01
When you Google most of the hit domains, many of them show up on "expired domain trackers", and above all Chinese expired domain trackers for some reason, notably e.g.:This suggests that scraping these lists might be a good starting point to obtaining "all expired domains ever".
- hupo.com: e.g. static.hupo.com/expdomain_myadmin/2012-03-06（国际域名）.txt. Heavily IP throttled. Tor hindered more than helped.Scraping script: cia-2010-covert-communication-websites/hupo.sh. Scraping does about 1 day every 5 minutes relatively reliably, so about 36 hours / year. Not bad.Results are stored under
tmp/humo/<day>.Check for hit overlap:The hits are very well distributed amongst days and months, at least they did a good job hiding these potential timing fingerprints. This feels very deliberately designed.grep -Fx -f <( jq -r '.[].host' ../media/cia-2010-covert-communication-websites/hits.json ) cia-2010-covert-communication-websites/tmp/hupo/*There are lots of hits. The data set is very inclusive. Also we understand that it must have been obtains through means other than Web crawling, since it contains so many of the hits.Some of their files are simply missing however unfortunately, e.g. neither of the following exist:webmasterhome.cn did contain that one however: domain.webmasterhome.cn/com/2012-07-01.asp. Hmm. we might have better luck over there then?2018-11-19 is corrupt in a new and wonderful way, with a bunch of trailing zeros:ends in:wget -O hupo-2018-11-19 'http://static.hupo.com/expdomain_myadmin/2018-11-19%EF%BC%88%E5%9B%BD%E9%99%85%E5%9F%9F%E5%90%8D%EF%BC%89.txt hd hupo-2018-11-19000ffff0 74 75 64 69 65 73 2e 63 6f 6d 0d 0a 70 31 63 6f |tudies.com..p1co| 00100000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 0018a5e0 00 00 00 00 00 00 00 00 00 |.........|More generally, several files contain invalid domain names with non-ASCII characters, e.g. 2013-01-02 contains365<D3>л<FA><C2><CC>.com. Domain names can only contain ASCII charters: stackoverflow.com/questions/1133424/what-are-the-valid-characters-that-can-show-up-in-a-url-host Maybe we should get rid of any such lines as noise.Some files around 2011-09-06 start with an empty line. 2014-01-15 starts with about twenty empty lines. Oh and that last one also has some trash bytes the end<B7><B5><BB><D8>. Beauty. - webmasterhome.cn: e.g. domain.webmasterhome.cn/com/2012-03-06.asp. Appears to contain the exact same data as "static.hupo.com"Also has some randomly missing dates like hupo.com, though different missing ones from hupo, so they complement each other nicely.Some of the URLs are broken and don't inform that with HTTP status code, they just replace the results with some Chinese text 无法找到该页 (The requested page could not be found):Several URLs just return length 0 content, e.g.:It is not fully clear if this is a throttling mechanism, or if the data is just missing entirely.
curl -vvv http://domain.webmasterhome.cn/com/2015-10-31.asp * Trying 125.90.93.11:80... * Connected to domain.webmasterhome.cn (125.90.93.11) port 80 (#0) > GET /com/2015-10-31.asp HTTP/1.1 > Host: domain.webmasterhome.cn > User-Agent: curl/7.88.1 > Accept: */* > < HTTP/1.1 200 OK < Date: Sat, 21 Oct 2023 15:12:23 GMT < Server: Microsoft-IIS/6.0 < X-Powered-By: ASP.NET < Content-Length: 0 < Content-Type: text/html < Set-Cookie: ASPSESSIONIDCSTTTBAD=BGGPAONBOFKMMFIPMOGGHLMJ; path=/ < Cache-control: private < * Connection #0 to host domain.webmasterhome.cn left intactStarting around 2018, the IP limiting became very intense, 30 mins / 1 hour per URL, so we just gave up. Therefore, data from 2018 onwards does not contain webmasterhome.cn data.Starting from2013-05-10the format changes randomly. This also shows us that they just have all the HTML pages as static files on their server. E.g. with:we see:grep -a '<pre' * | s2013-05-09:<pre style='font-family:Verdana, Arial, Helvetica, sans-serif; '><strong>2013<C4><EA>05<D4><C2>09<C8>յ<BD><C6>ڹ<FA><BC><CA><D3><F2><C3><FB></strong><br>0-3y.com 2013-05-10:<pre><strong>2013<C4><EA>05<D4><C2>10<C8>յ<BD><C6>ڹ<FA><BC><CA><D3><F2><C3><FB></strong> - justdropped.com: e.g. www.justdropped.com/drops/010112com.html. First known working day:
2006-01-01. Unthrottled. - yoid.com: e.g.: yoid.com/bydate.php?d=2016-06-03&a=a. First known workding day:
2016-06-01.
Data comparison:
- 2012-01-01Looking only at the
.com:The lists are quite similar however.- webmastercn has just about ten extra ones than justdropped, the rest is exactly the same
- justdropped has some extra and some missing from hupo
We've made the following pipelines for hupo.com + webmasterhome.cn merging:
./hupo.sh &
./webmastercn.sh &
./justdropped.sh &
wait
./justdropped-post.sh
./hupo-merge.sh
# Export as small Google indexable files in a Git repository.
./hupo-repo.sh
# Export as per year zips for Internet Archive.
./hupo-zip.sh
# Obtain count statistics:
./hupo-wc.shCount unique domains in the repos:
( echo */*/*/* | xargs cat ) | sort -u | wcThe extracted data is present at:Soon after uploading, these repos started getting some interesting traffic, presumably started by security trackers going "bling bling" on certain malicious domain names in their databases:
- archive.org/details/expired-domain-names-by-day
- github.com/cirosantilli/expired-domain-names-by-day-* repos:
- github.com/cirosantilli/expired-domain-names-by-day-2006
- github.com/cirosantilli/expired-domain-names-by-day-2007
- github.com/cirosantilli/expired-domain-names-by-day-2008
- github.com/cirosantilli/expired-domain-names-by-day-2009
- github.com/cirosantilli/expired-domain-names-by-day-2010
- github.com/cirosantilli/expired-domain-names-by-day-2011 (~11M)
- github.com/cirosantilli/expired-domain-names-by-day-2012 (~18M)
- github.com/cirosantilli/expired-domain-names-by-day-2013 (~28M)
- github.com/cirosantilli/expired-domain-names-by-day-2014 (~29M)
- github.com/cirosantilli/expired-domain-names-by-day-2015 (~28M)
- github.com/cirosantilli/expired-domain-names-by-day-2016
- github.com/cirosantilli/expired-domain-names-by-day-2017
- github.com/cirosantilli/expired-domain-names-by-day-2018
- github.com/cirosantilli/expired-domain-names-by-day-2019
- github.com/cirosantilli/expired-domain-names-by-day-2020
- github.com/cirosantilli/expired-domain-names-by-day-2021
- github.com/cirosantilli/expired-domain-names-by-day-2022
- github.com/cirosantilli/expired-domain-names-by-day-2023
- github.com/cirosantilli/expired-domain-names-by-day-2024
- GitHub trackers:
- admin-monitor.shiyue.com
- anquan.didichuxing.com
- app.cloudsek.com
- app.flare.io
- app.rainforest.tech
- app.shadowmap.com
- bo.serenety.xmco.fr 8 1
- bts.linecorp.com
- burn2give.vercel.app
- cbs.ctm360.com 17 2
- code6.d1m.cn
- code6-ops.juzifenqi.com
- codefend.devops.cndatacom.com
- dlp-code.airudder.com
- easm.atrust.sangfor.com
- ec2-34-248-93-242.eu-west-1.compute.amazonaws.com
- ecall.beygoo.me 2 1
- eos.vip.vip.com 1 1
- foradar.baimaohui.net 2 1
- fty.beygoo.me
- hive.telefonica.com.br 2 1
- hulrud.tistory.com
- kartos.enthec.com
- soc.futuoa.com
- lullar-com-3.appspot.com
- penetration.houtai.io 2 1
- platform.sec.corp.qihoo.net
- plus.k8s.onemt.co 4 1
- pmp.beygoo.me 2 1
- portal.protectorg.com
- qa-boss.amh-group.com
- saicmotor.saas.cubesec.cn
- scan.huoban.com
- sec.welab-inc.com
- security.ctrip.com 10 3
- siem-gs.int.black-unique.com 2 1
- soc-github.daojia-inc.com
- spigotmc.org 2 1
- tcallzgroup.blueliv.com
- tcthreatcompass05.blueliv.com 4 1
- tix.testsite.woa.com 2 1
- toucan.belcy.com 1 1
- turbo.gwmdevops.com 18 2
- urlscan.watcherlab.com
- zelenka.guru. Looks like a Russian hacker forum.
- LinkedIn profile views:
- "Information Security Specialist at Forcepoint"
Check for overlap of the merge:
grep -Fx -f <( jq -r '.[].host' ../media/cia-2010-covert-communication-websites/hits.json ) cia-2010-covert-communication-websites/tmp/merge/*Next, we can start searching by keyword with Wayback Machine CDX scanning with Tor parallelization with out helper cia-2010-covert-communication-websites/hupo-cdx-tor.sh, e.g. to check domains that contain the term "news":produces per-year results for the regex term OK lets:
./hupo-cdx-tor.sh mydir 'news|global' 2011 2019news|global between the years under:tmp/hupo-cdx-tor/mydir/2011
tmp/hupo-cdx-tor/mydir/2012./hupo-cdx-tor.sh out 'news|headline|internationali|mondo|mundo|mondi|iran|today'Other searches that are not dense enough for our patience:
world|global|[^.]infoOMG and a few more. It's amazing.
news search might be producing some golden, golden new hits!!! Going full into this. Hits:- thepyramidnews.com
- echessnews.com
- tickettonews.com
- airuafricanews.com
- vuvuzelanews.com
- dayenews.com
- newsupdatesite.com
- arabicnewsonline.com
- arabicnewsunfiltered.com
- newsandsportscentral.com
- networkofnews.com
- trekkingtoday.com
- financial-crisis-news.com
D'oh.
But to be serious. The Wayback Machine contains a very large proportion of all sites. It does happen sometime that a Wayback Machine archive is missing or broken and cqcounter has the screenshot. But the Wayback Machine is still the most complete database we have found so far. Some archives are very broken. But those are rare.
The only problem with the Wayback Machine is that there is no known efficient way to query its archives across domains. You have to have a domain in hand for CDX queries: Wayback Machine CDX scanning.
The Common Crawl project attempts in part to address this lack of querriability, but we haven't managed to extract any hits from it.
CDX + 2013 DNS Census + heuristics however has been fruitful however.
We have dumped all Wayback Machine archives of known websites to: github.com/cirosantilli/cia-2010-websites-dump using cia-2010-covert-communication-websites/download-websites.sh. This allows for better grepping and serves as a backup in case they ever go down.
You can then interact with it via the Bitcoin CLI client.
Endohedral Fullerenes by Dom Burges (2016)
Source. Using funds from block 9.
A random field you add to make something transform locally the way you want. See e.g.: Video "Deriving the qED Lagrangian by Dietterich Labs (2018)".
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