The DHCP_IPV6_ADDRESS structure contains the IPv6 address. This is used in the DHCP_OPTION_SCOPE_INFO6 (section 2.2.1.2.30) structure.

 typedef struct _DHCP_IPV6_ADDRESS {
   ULONGLONG HighOrderBits;
   ULONGLONG LowOrderBits;
 } DHCP_IPV6_ADDRESS,
  *LPDHCP_IPV6_ADDRESS,
  *PDHCP_IPV6_ADDRESS;

HighOrderBits: This is of type ULONGLONG, containing the higher 64 bits of the IPv6 address.

LowOrderBits: This is of type ULONGLONG, containing the lower 64 bits of the IPv6 address.