Crystal confusion leads to retractions for optics researchers

A mistaken molecular structure has led to a retraction and a withdrawal for group in India studying optical crystals.

Here’s the notice for “Crystal growth and spectroscopic characterization of Aloevera amino acid added lithium sulfate monohydrate: A non-linear optical crystal” in Spectrochimica Acta Part A:

This article has been retracted at the request of authors.

According to the author we have reported Aloevera Amino Acid added Lithium sulphate monohydrate [AALSMH] crystal is a new nonlinear optical crystal. From the recorded high performance liquid chromatography spectrum, by matching the retention times with the known compounds, the amino acids present in our extract are identified as homocystine, isoleucine, serine, leucine and tyrosine. From the thin layer chromatography and colorimetric estimation techniques, presence of isoleucine was identified and it was also confirmed by NMR spectrum. From the above studies, we came to conclude that AALSMH is new nonlinear optical crystal. After further investigation, lattice parameter values of AALSMH are coinciding with lithium sulphate. Therefore we have decided to withdraw our paper. Sorry for the inconvenience and time spent.

A comment on the March 2014 article was published in July. Here’s the abstract:

The title paper (Manimekalai et al., 2014) reports a slow evaporation solution growth of a so called ‘Aloevera amino acid added lithium sulfate monohydrate’ (AALSMH) crystal. In this communication, many points of criticism, concerning the crystal growth, NMR spectrum and X-ray powder pattern of this so called AALSMH nonlinear optical crystal are highlighted.

Another paper by the group, “Investigations on growth, phytochemical and optical analyses of Aloe Barbadensis’s amino acid added potassium dihydrogen phosphatenonlinear optical crystals,” is listed as “withdrawn at the request of the author” from Optik as of December 2013. We’ve written about Elsevier’s withdrawal policy before – a paper published ahead of print can be disappeared from the internet, without an explanation.

Here’s that policy, as stated on the withdrawal notice:

Withdrawn Articles in Press are proofs of articles which have been peer reviewed and initially accepted, but have since been withdrawn before being published in this publication. Reasons for withdrawal may be a decision by the author and/or editor, accidental duplication of an article elsewhere or because the content contravenes the Elsevier publishing policy in some way. Withdrawn Articles in Press are only visible to users when following an external link, e.g., a PubMed or DOI link. Such Withdrawn Articles in Press are not searchable or otherwise available in ScienceDirect.

We’ve reached out to the author and the editor, and will update with any new information.