# Tag Info

14

This sounds like you were exploring work at least related to the work by the Lilienfeld group equally hosting a dedicated site here about data sets already used in their earlier and ongoing exploration of chemical space, programs used to work with the data, and publications. To go considerably higher in molecule count than QM9, you could either go for GDB-...

11

The ISOL24 database (http://www.thch.uni-bonn.de/tc.old/downloads/GMTKN/GMTKN55/ISOL24.html) contains molecules with up to 81 atoms! The other answer says that there's a database called "OE" with molecules that have up to 174 atoms, but it is "not yet publicly available".

9

NIST webbook does have a lot of data, though they are not in any kind of an API form as far as I know. http://webbook.nist.gov/chemistry/

8

CIF contains coordinates for the atoms in asymmetric unit only (what Ivan called "the independent part" in the comments), plus the set of symmetry operation to fill the remaining space with those atoms. What you want to do is to open CIF in any viewer supporting that format, make sure the unit cell is packed, e.g. the symmetry operations are applied along ...

8

NIST is the best place to turn for lots of data. However, more easily parsed, smaller datasets are available in a couple of other locations. The CHNOSz package in R has thermochemical data for a variety of species, mostly inorganic. Their database is referenced back to the chemical literature. See an answer I gave to an old question for an example of how ...

8

Only for a diatomic molecule and only assuming the vibration is harmonic. In this case, $\mathrm{ZPVE}=\omega_1/2$. If its anharmonic or has rovibrational coupling, even the expression for a diatomic doesn't not allow you to determine $\omega_1$ from just the ZPVE. With polyatomic molecules, the ZPVE has contributions from all the vibrations, so you can't ...

7

I am aware of this range diagram about $\ce{^{81}Br}$ that appeared in the recurrent (open access) IUPAC recommendations of atomic weights in Pure and Applied Chemistry: (source: doi 10.1351/PAC-REP-13-03-02) which cites data of a publication in Environmental Chemistry extending a little to $\ce{^{37}Cl}$ (doi 10.1071/EN10090, open access), too. Even if ...

7

As a quick fix: To access the IR spectral data of $\ce{HCl}$, I opted for a seach by (Hill) formula on NIST's web page, which yielded three entries here. For $\ce{HCl}$ in particular (here) I opted for the first one here, indeed offering the spectrum as image file or as JCAMP-DX. As in the comment by @EdV, this JCAMP-DX an ASCII file indeed. Note JDXview ...

6

In the current form the question is addressed, and assuming you took a look at a listing of software already in the field like here, I speculate the sheer number of organic reactions (just some) alone renders such a task as a one-man / one-woman project too large. There is a lot of work associated to create such a database, or software. Organic Synthesis is ...

6

Beyond other answers, I'd suggest the original PubChemQC project, which offers ~3 million molecules from PubChem optimized using DFT (B3LYP/6-31G*). Molecules include a wide variety of elements as long as the molecular mass is less than 500 Da. (Roughly speaking that should still handle ~38 carbon atoms.) "PubChemQC Project: A Large-Scale First-Principles ...

5

According to the Franck-Condon principle which you are implicitly referring to, absorption is indeed very fast compared to all other processes. If you are looking for time scales of photophysical processes, I can suggest you for example B. Valeur's book "Molecular Fluorescence: Principles and Applications", chapter 3 (Characteristics of fluorescence ...

5

Reference 1 reports the isomerization barrier for N‐methylacetohydroxamic acid. From the abstract: We have now determined the activation barrier to C–N rotation from major to minor conformation of a small secondary HA in $\ce{D2O}$ to be 67.3 kJ/mol. The HA rotational barrier scales with solvent polarity, as is observed in amides, although the HA barrier ...

4

What you have provided is a definition of all the terms involved. This is fine, but there remains the (rather interesting) question of exactly how this is defined for a molecule in silico, especially because your question asks specifically about the GDB-13 database. Of course, one could evaluate "synthetic accessibility" by trying to make it in the lab: if ...

4

The primary reference for this type of data is the article by Li [1]. Snyder cites this paper as the primary source for UV cutoff values ("Ref 7" on the screenshot below) [2, p. 299]: References Li, J. B. Signal-to-Noise Optimization in HPLC UV Detection. LC GC 1992, 10 (11), 856–864. Snyder, L. R.; Kirkland, J. J.; Glajch, J. L. Practical HPLC ...

3

After looking through the sources from the gratefully acknowledged Buttonwood's answer, I also came across CIAAW, which seems to have some of the best available data for the natural isotope abundance ranges of elements like $\ce{C}$, $\ce{H}$, $\ce{N}$, $\ce{O}$, and $\ce{Cl}$. It is based on IUPAC Technical Report 2013 [1]. References Meija, J.; Coplen, T....

3

The usual reference for phase change information, for various substances, is Perry's Chemical Engineers' HandBook by Perry and Green. Then there are the CRC HandBooks and sometimes such information can be gleaned from the Chemical Engineering Encyclopedias (I forget their names now). Then IUPAC, NIST and some other governemntal institutions make such ...

3

Chemical nomenclature is officially defined by IUPAC (International Union of Pure and Applied Chemistry). You can find most IUPAC names for these terpenic compounds by searching their popular names on Wikipedia, they are quite long and confusing terms though, and can only be interpreted if you have a certain knowledge in organic/inorganic chemistry. What ...

3

Until 2005 or 2006 the best source was Chemical Market Reporter. It had the form of a newspaper and was edited once a week. The last pages listed market prices for commodities, some speciality chemicals and also agricultural products. Hundreds of products were listed and you had some idea of what were the options you had for designing an industrial ...

3

I never ran into uv absorption data for (aqueous) sulfuric acid and I doubt that there is any absorption at $\lambda$ = 508 nm. There is an old paper by K. F. Palmer and D. Williams in Appl. Optics, 1975,14, 208-219 (DOI) on the optical properties of sulfuric acid droplets with respects to the composition of clouds on Venus and a more recent one from the ...

3

I personally find SMILES quite unreadable, even for only small compounds. I think they are even less readable when performing substitutions. Given the vast amount of special characters they use, I do not think they are a good way to create a naming scheme. An alternative is using InChIkeys but since they are not human readable, I want to avoid that option....

3

According to Xemistry, PubChem uses Cactvs for 2D layout coordinate computation. A friend pointed this out to me. If you scroll to the bottom of the CACTVS Toolkit FAQ (http://www.xemistry.com/docs.htm), it says the following: Interesting. I did not know that PubChem is built with Cactvs. I heard it was implemented with OpenEye's OEChem library. Well, that ...

3

I completely agree with @porphyrin comment. This is an example of crystal data which formatting does not entirely meet IUCr requirements, that's all. This happens a lot, and in most cases it's no big deal. This particular set of coordinates is just not uniform within a single cell. Different crystallographic software uses different means to "reassemble" ...

3

One resource you can use is the Crystallography Open Database. Search for structures with two elements O and H, and named “ice”. You will then find several experimental structures for cubic ice: with downloadable structure files in CIF format: 1, 2. These were done from X-ray diffraction studies and only feature heavy atoms (oxygen) positions. Although I ...

3

Possibly Avogadro may deserve a test complementary to the suggestions by @andselisk, too. Similar as @andselisk, I accessed the 25 degC *.cif data set about Pyrope by Meagher1975 at AMCSD. Already the very first automatic display of the data was the one about an unit cell depicted below: The program may be of interest for you since it allows to save this ...

3

There are several databases of thermochemical properties, a number of them being listed on this Wikipedia page (at the bottom). Most of them are not freely available online, but require subscription. I've searched online but couldn't find that information freely available. Another possible way to get the information would be through a search of the ...

3

For the Elsevier's Reaxys data base, there is a support page you may consult without subscription, nor log-in to the product. Actually, this is more like a searchable directory, too, because you search for keywords, like «rank», too. Doing so here -- time stamped 25/04/2019 -- offers insight about «How do I view my results?». About half-way through this ...

3

The nearest I came to an explanation is an article (Ref. 1) by authors of the database explaining that, in the case of $\ce{H2O (cr,l)}$, the notation (cr,l) refers to the condensed state. Also, a link from the above data page explains that "cr=crystal" and "l=liquid" (thanks MaxW for hinting at the solution). A further update: it finally dawned on me that ...

2

Free Energy and Enthalpy Database (FREED) This has proved extremely valuable (at least for me) and I think that others can also benefit from this.

2

Since you're a Dutch neighbour, the European Chemicals Agency might be an option.

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