Journal of Magnetism and Magnetic Materials 265 (2003) 296–304 Influence of magnetic field on the growth and properties of calcium tartrate crystals K.V. Saban*, T. Jini, G. Varghese Crystal Physics Centre, St. Berchmans’ College, Changanassery, Kerala 686 101, India Received 22 August 2002 Abstract The growth of calcium tartrate crystals in hydrosilica gel, in the presence of static magnetic fields has been investigated. Crystal formation at the free surface of the gel was studied under fields of strength up to 3 T. Weak magnetic fields created by permanent ferrite magnets were used to study the crystal formation in the gel column over long duration. The XRD spectra of the samples grown under magnetic fields exhibit increase in d values of most of the diffraction peaks and noticeable change in the intensity of reflections from certain planes. Application of the field resulted in the appearance of two additional absorption peaks in the IR spectrum of the material. Samples grown under fields of strength 1 and 3 T show paramagnetism up to 6 and 7 T, respectively, of the probing field strength. For stronger probing fields, the samples start exhibiting diamagnetism. r 2003 Elsevier Science B.V. All rights reserved. PACS: 81.10.Dn; 83.50.Pk; 81.40.Rs Keywords: Magnetic effect; Gel growth; Calcium tartrate; XRD spectrum; IR spectrum; Magnetic susceptibility 1. Introduction A recent review article [1] presents the manifold changes brought about by the presence of mag- netic fields on the nucleation and growth of a variety of materials. These findings indicate that magnetic fields can be used for the design of materials with improved properties [2]. Since the actual mechanism by which magnetic fields affect crystallization and material properties is still unknown, there is a timely need for extensive research in this field. Fields can influence the size, nucleation rate, thermal stability, quality and lattice spacing of crystals [3,4]. The following examples illustrate that the nature of the impact depends on the material used in a particular experiment. The presence of magnetic fields during the crystal- lization of Fe(NH 4 ) 2 (SO 4 ) 2  6H 2 O, Ni(NH 4 ) 2 - (SO 4 ) 2  6H 2 O and Co(NH 4 ) 2 (SO 4 ) 2  6H 2 O resulted in the increase of growth rate [5–7]. In the case of AlK(SO 4 ) 2  6H 2 O, Zn(NH 4 ) 2 (SO 4 ) 2  6H 2 O and Cu(NH 4 ) 2 (SO 4 ) 2  6H 2 O [6] field did not have any influence on the growth rate. On the other hand, the growth rate of ADP [8] and Rochelle salt [9,10] ARTICLE IN PRESS *Corresponding author. Tel.: +91-481-428246; fax: +91- 481-411472. E-mail address: sabanvarkey@rediffmail.com (K.V. Saban). 0304-8853/03/$ - see front matter r 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0304-8853(03)00278-6