Nikolay Tumanov

@ntumanovxray

A crystallographer at UNamur, SC and PXRD. Structures, cookies and 3D-printing. A crystallographer by day, a food supplements forensic expert by the night.

523 Siguiendo1262 Seguidores2044 Publicaciones

Bluesky

¿Es tu perfil?Reclámalo y ntumanovxray.dirty.social es tuyo.Reclamar perfil

Nikolay Tumanov@ntumanovxray· 1d

Well, that is not exactly correct… Arriving at #IUCr2026

Nikolay Tumanov@ntumanovxray· 3d

Ah, these beautiful Canadian 🇨🇦 beaches - clean water, sand, a cup of tea, bear spray and couple of grizzlies (photographed later from the car when we were leaving the beach).

A cup of tea (rubbish one) and a bear spray on sand .

A grizzly bear near Jasper, Alberta, Canada.

Nikolay Tumanov@ntumanovxray· 25d

"Fake of the Day" Part 10. Magnesium Taurate from KAL. This product contains no magnesium taurate, only taurine, brucite and periclase. That is the company that cannot interpret PXRD pattern. #chemsky #TaurateCurse #SupplementsSaga #fraud #PXRD

$A powder diffraction pattern of a food supplement "Magnesium taurate" https://www.naturitas.be/p/complements/mineraux-et-oligoelements/magnesium/taurate-de-magnesium-400-b6-90-comprimes-kal, that in reality is a mixture of taurine periclase and brucite.$

Nikolay Tumanov@ntumanovxray· 25d

"Fake of the Day" Part 9. Magnesium Taurate from viridian. This product contains no magnesium taurate, only taurine and hydromagnesite, at least nothing weird. (Data send, they are investigating) #TaurateCurse #SupplementsSaga #fraud #PXRD

Nikolay Tumanov@ntumanovxray· 27d

Ah, forgot previous one. "Fake of the Day" Part 7. Magnesium Taurate from Therascience. This product contains no magnesium taurate, only taurine and brucite. At least nothing strange, it is not the worst case. Send data, zero response.

$A powder diffraction pattern of a food supplement "Magnesium taurate" https://www.therascience.com/fr_be/magnetaurate-phy466b.html, that in reality is a mixture of taurine and brucite.$

Nikolay Tumanov@ntumanovxray· 27d

"Fake of the Day" Part 8. Magnesium Taurate from vit4ever. This product contains no magnesium taurate, only taurine, magnesium oxide and small amount of hexahydride. As usual reminder for this series - magnesium taurate does not exist in reality. #TaurateCurse #SupplementsSaga #fraud #PXRD

$A powder diffraction pattern of a food supplement "Magnesium taurate", that in reality is a mixture of taurine, periclase and hexahydrite.$

Nikolay Tumanov@ntumanovxray· 28d

“It is definitely just a phosphine” (tm) How can you “accidentally” add selenium? #chemsky #crystallography

Nikolay Tumanov@ntumanovxray· Jul 10

A week without a phosphine oxide is a wasted week, but this time not from the traditional supplier phosphine oxides. We were not the only one, the structure is known since 2022. #chemsky #chemchat #crystallography

A preliminary structure of a phosphine oxide, an oxidized catalyst from a failed reaction.

Nikolay Tumanov@ntumanovxray· Jul 10

"Fake of the Day" Part 6. Magnesium Taurate from Cosmo Pharm. This bottle brings a new mineral to my collection - Kieserite. #supplements #chemsky #TaurateCurse #SupplementsSaga

$A powder diffraction pattern of a food supplement "Magnesium taurate", that in reality is a mixture of taurine, periclase, hexahydrite and kieserite.$

Nikolay Tumanov@ntumanovxray· Jul 9

"Fake of the Day" Part 5. Magnesium Taurate from Holland & Barrett. Ah, this is a classic - physical mixture of taurine and hydromagnesite, no magnesium taurate. One of the safest kind of fakes, at least it will not give you a run for a toilet. #supplements #chemsky #TaurateCurse #SupplementsSaga

$A powder diffraction pattern of "magnesium taurate" food supplement https://www.hollandandbarrett.be/fr/shop/product/holland-barrett-expert-magnesium-taurate-90-capsules-6100001108, that contains only physical mixture of the taurine and hydromagnesite.$

Nikolay Tumanov@ntumanovxray· Jul 8

"Fake of the Day" Part 4. Magnesium Taurinate from BLDpharm. www.bldpharm.com/products/927... This is an exception in this series, because is it not a food supplement with "magnesium taurate", but a "pure" compound from chemical supplier. #supplements #chemsky #TaurateCurse #SupplementsSaga

Nikolay Tumanov@ntumanovxray· Jul 7

"Fake of the Day" Part 3. "Magnesium Taurate avec P-5-P from" Vitakruid. To add something not so boring as previous cases - this is a record-holder for the moment, I was able to identify 4 distinct minerals! Minerals in the strict IMA definition. #TaurateCurse #SupplementsSaga #chemsky

Nikolay Tumanov@ntumanovxray· Jul 6

Fake of the Day, part 2. TAURAPRO from Pronesium - no magnesium taurate, only taurine and brucite (magnesium hydroxide). Boring, except bold claims about superior USA ingredients. #chemsky #TaurateCurse #SupplementsSaga

$Results of powder X-ray diffraction analysis of a food supplement https://pronesium.com/en-be/products/taurapro-magnesiumtaurat?variant=50991259582728, showing that it contains undeclared taurine and magnesium hydroxide, no magnesium taurate.$

Nikolay Tumanov@ntumanovxray· Jul 5

Do diffraction, have fun, they say... @stecanossa.bsky.social , an analysis by single picture? :) #crystallography #chemsky

$Single-crystal X-ray diffraction with a lot of diffuse scattering.$

Nikolay Tumanov@ntumanovxray· Jul 5

Ok, I cannot resist it and went on a shopping spree, so you know who to blame for following series of post (one per day). So, here we go, Fake of the Day, part 1. That product contains some herbal stuff, but I still was able to analyze it - contains undeclared taurine and magnesium oxide. 1/3

$Results of powder X-ray diffraction analysis of a food supplement https://medi-market.be/fr/c/pure-somnia-v-60-capsules/p/289443, showing that it contains undeclared taurine and magnesium oxide.$

Nikolay Tumanov@ntumanovxray· Jul 2

I thought that I am done with buying (and refunding, so) fake magnesium taurate supplement, but that stuff looks so tempting... "pure, oxide-free raw material from the USA", in fact, "made in USA" is rather a huge red flag, from my expirience. #chemsky #TaurateCurse #SupplementsSaga

Nikolay Tumanov@ntumanovxray· Jul 2

Looks suspicious, right? But these are false alerts, cased by sc-to-sc phase transition at low temperature from "normal" P2₁/c and Z'=1 at room temperature to P2₁ and Z=4 at 100 K. #chemsky #crystallography

Nikolay Tumanov@ntumanovxray· Jul 1

We a have greed one too!

Nikolay Tumanov@ntumanovxray· Jul 1

Oh, that is new, if I am not mistaken. And I like it. #crystallography

PLAT089 Type_3 Test for reasonable data / parameter ratio (non-centro) (Zmax <= 18)
The data/parameter ratio of a quality structure determination in a
non-centrosymmetric space-group containing atoms with Z less than 19 is
expected to be higher than 7. This ratio can be improved by refining
Hydrogen atoms bonded to Carbon riding on their carrier atom. The number
of reflections used in this ratio is that of the Laue averaged set.
validation test criteria used are expected to be met with a dataset complete
with a resolution sin(theta)/lambda >= 0.6 Ang-1.
Hydrogen atom parameters are often meaningfully refined with OLEX2/NoSphereA2
non-spherical scattering factors. In that case a G-Alert is issued with data
resolution >= 0.6 Ang-1 and data/parameter ratio > 5 and <= 7.

Nikolay Tumanov@ntumanovxray· Jul 1

But definitely not always:

Residual electron density of disordered hexane.

Nikolay Tumanov@ntumanovxray· Jul 1

Not so many members of Team Hexane around to annoy me often. And look hexane is well-behaving molecule! ⬇️

A fragment of crystal structure with well-ordered hexane.

Nikolay Tumanov@ntumanovxray· Jun 30

Each time a fresh organic student fricking out from the image disordered methyl group in his/her structure. #chemsky #crystallography

A fragment of crystal structure with disordered CH3 group, giving an impression that it is CH6 group.

Nikolay Tumanov@ntumanovxray· Jun 30

Weird coincidence: I never heard about oxime before @xtalgrrl.bsky.social mentioned it and than one month later it appear in a structure. #chemsky #crystallography

A fragment of crystal structure with an oxime group.

Nikolay Tumanov@ntumanovxray· Jun 29

A PhD student in organic synthesis who is at the end of her PhD: "I have a lot of intermediate products that already characterised, but it would nice to have X-ray structure". Well, it did not go so simple. Behold a molecule, definitely without heavy atoms! #crystallography #chemsky #RealTimeChem

Jennifer Lawrence with a molecule of 2-bromo-1,3-dimethoxybenzene

Nikolay Tumanov@ntumanovxray· Jun 22

Well, that was fast.

Nikolay Tumanov@ntumanovxray· Jun 21

@b-kajetan.bsky.social is back to his favorite hobby - crystallizing high-quality crystals of beta-CD hydrate. It is fifth dataset of beta-CD for me this year. The problem that you need to collect enough data to understand that it is not good.

A preliminary crystal structure of beta-CD hydrate. Again.

Nikolay Tumanov@ntumanovxray· Jun 20

"Well, yes, we have a mechanism to suggest a revision to the European Pharmacopoeia via national pharmacopoeia authority, but it the first time when somebody send such request..."

from the page https://www.edqm.eu/en/submitting-drafts-and-requests-for-revision

Submitting drafts and requests for revision
The European Pharmacopoeia Commission encourages you to submit draft monographs or General Chapters. Your draft may be the starting point for what could become an official public standard.

You can also propose revisions to a general chapter or monograph already published in the European Pharmacopoeia. To ensure that your proposal receives the attention it deserves, please make sure that you highlight the suggested changes clearly. You are also invited to submit any data you may have in support of your proposal.

How can I propose a new monograph or submit a request for revision?
For manufacturers and other interested parties from Member States of the Ph. Eur. Convention: via the national pharmacopoeia authority.
For others (manufacturers and other interested parties from non-Member States of the Ph. Eur. Convention or multinational interested parties, for international organisations and for industry associations or other associations): via the Secretariat in Strasbourg (via the EDQM HelpDesk)
Download the form to request the revision of a monograph or general chapter.

Nikolay Tumanov@ntumanovxray· Jun 19

I was not trying yet. But I thin something like this will work:

$S2. Experimental A solution of taurine (1.0 mmol) and KOH (1.0 mmol) in anhydrous methanol (10 ml) was added slowly to a solution of Ni(CH3COO)2 (1.0 mmol) in anhydrous methanol (10 ml). After stirring for 10 min, it was then dropped into a 25 ml Teflon-lined stainless steel reactor and heated at 393 K for five days. Thereafter, the reactor was slowly cooled to room temperature and green block-shaped crystals suitable for X-ray diffraction were collected.$

Nikolay Tumanov@ntumanovxray· Jun 19

Real old-school #crystallography - we tried to solve a structure with intuition and only then we turn to a computer. #chemsky

Solution of the structure

An initial attempt at solving the structure intuitively
from a sharpened three.dimensi0nal Patterson map
was unsuccessful. A numerical superposition algorithm
based on the Buerger minimum function was then
coded for machine computation.

Nikolay Tumanov@ntumanovxray· Jun 18

Today I unexpectedly received a parcel with this supplement - for free. Well, thanks, another point to my collection. They corrected the label on the bottle, good point. But the product itself is a fake - taurine and magnesium hydroxide. #Chemsky #chemchat #SupplementsSaga #TaurateCurse