Color properties of model spin chain materials: VOHPO412H2O and (VO)2P2O7

Journal Article · Tue Jan 01 04:00:00 EST 2008 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.77.165111· OSTI ID:968252

Cao, J. ^[1]; Musfeldt, J. L. ^[1]; Singh, David J ^[2]; Rahaman, B ^[3]; Saha-Dasgupta, Tanursi ^[4]; Torardi, C. C. ^[5]; Sales, Brian C ^[2]; Christen, Hans-Martin ^[2]; Swader, Onome A ^[2]

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1. University of Tennessee, Knoxville (UTK)
2. ORNL
3. Bose Centre
4. S. N. Bose National Centre for Basic Sciences, Kolkata, India
5. DuPont Company

We report the optical properties of two prototypical S=1/2 magnetic materials: vanadyl (IV) hydrogen-phosphate hemihydrate VOHPO{sub 4} {center_dot} H{sub 2}O and its derivative vanadyl pyrophosphate (VO){sub 2}P{sub 2}O{sub 7}. Local density approximation electronic structure calculations are used to identify and evaluate correct structures, assign the observed excitations, and quantify bonding and hybridization effects in both materials. VOHPO{sub 4} {center_dot} H{sub 2}O displays a strong color band that is derived from V{sup 4+} d {yields} d excitations. It is sensitive to both the local vanadium environment and the enhanced low-temperature hydrogen bonding between layers. In contrast, (VO){sub 2}P{sub 2}O{sub 7} displays a diffuse and gradually rising near infrared absorption in all directions. The O p {yields} V d charge transfer gaps in both materials are similar. We predict that the on-site excitations of the transition metal centers may be sensitive to a magnetic state via a magnetic field control of p-d hybridization.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 968252
• Journal Information: Physical Review B, Journal Name: Physical Review B Journal Issue: 16 Vol. 77; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
ABSORPTION
APPROXIMATIONS
BONDING
ELECTRONIC STRUCTURE
HYBRIDIZATION
HYDROGEN
MAGNETIC FIELDS
MAGNETIC MATERIALS
OPTICAL PROPERTIES
PYROPHOSPHATES
SPIN
TRANSITION ELEMENTS
VANADIUM